Priority and Severity in Testing.

Severity and Priority in Testing?

As usually, Tester select Severity of bugs and Project lead or project manager selects bug priority.

Priority - Priority is the order in which developer has to fix the bug.
Severity - Severity is how seriously the bug is impacting the application.

Eg.

High Priority & High Severity: A show stopper error which occurs on the basic functionality of the application. (Eg. A site maintain the student details, on saving record if it, doesn't allow to save the record then this is high priority and high severity bug.)

High Priority & Low Severity: The spell mistakes that happens on the cover page or heading or title of an application.

High Severity & Low Priority: The application generates a show stopper or system error, (for which there is no workaround) but on click of link which is rarely used by the end user.

Low Priority and Low Severity: Any cosmetic or spell issues which is with in a paragraph or in the report (Not on cover page, heading, title).

Severity:

Severity is an indicator of the impact of the defect on the software. For example, let us assume you have a web application where the user clicks on a rarely used link and it crashes. Then, the defect is said to be having high severity even though the chances of the user clicking on the link is rare.

Different Severity Levels:

·         Critical: If a defect causes the termination or complete shut-down of the application, then its severity is “Critical”.

·         Major: If the defect results in the termination of the system but there exist one or more alternative methods to achieve the desired results or use the system, then the defect is said to have the severity level “Major”.

·         Moderate: The severity of the bug will be “Moderate” when the defect in the system does not cause the program to terminate but produces results that are not correct or inconsistent.

·         Minor: A defect is of severity “Minor” when the usability or functionality of the system is not affected much but must be fixed. The results are obtained by small corrections and there is no break-down of the system caused by the defect.

·         Cosmetic: Defects that are related to the look and feel of the system are given the severity “Cosmetic”

What is Priority?

Priority is considered from the customer’s point of view. Priority indicates how soon the defect needs to be fixed by the developer. Priority is set by the product manager/customer and it determines the time frame given to the developer to fix the bug.

Different Levels of Priority:

·         Low: A defect that can be deferred or fixed in the later stages once the higher priority ones are fixed, as it is not serious from the requirement point of view is of low priority.

·         Medium: A defect that needs to be fixed during the normal course of development activity is given the status as “Medium”. Such defects occur when a particular feature cannot be used the way it should be because of some environmental issue, defect in the program, or some code that has to be added. Usually, these defects are fixed and delivered to the testing team as a part of a new release.

·         High: Those defects that need to be fixed as soon as possible so that the testing team can continue with the testing are said to be of high priority. The core functionality fails as a result of such defects and the system cannot be tested or used until the defect is fixed.

High Severity and  High Priority:

You log in to your amazon.com account, add items to the cart and click “Proceed to Checkout” button. You make the payment and the system crashes. This defect makes the whole buying functionality unusable and so the severity is high. The basic purpose of amazon.com is to buy and sell products and most of the customers are affected by this. So, this defect is of high priority which must be fixed immediately for the buying process to work.

Low Severity and High Priority:

Suppose, that in the amazon.com website, the logo is displayed as ”amazn.com” with the letter “o” missing. This defect does not affect the buying/selling or any other functionality in any way. So, the severity of this defect is low. But, a mistake in the company logo affects the brand identity and impacts the user experience. So, the defect is of high priority.

Low Severity and Low Priority:

Suppose the tester clicks on the “Conditions of Use” hyperlink at the bottom of the amazon.com homepage. If there is an alignment issue in the text displayed or if there is a spelling mistake in the content displayed, the defect is said to be of low priority because people rarely read this page and it does not impact the user experience. The severity is also low because the functionality of the application is not affected.

1)High Severity and Low priority --> application doesn't allow customer expected Configuration.

2)High severity and High priority -->Application doesn't allow multiple users.

3)Low severity and High Priority --> No error message to prevent wrong operation.

4)Low severity and Low priority -->Error message is having complex meaning

Defect Priority and Severity Levels

Posted ON 10 Jun

Priority and severity level of defects needed to be defined as the development team cannot resolve all defects simultaneously. The test team needs to indicate how soon they want to get the defect fixed, and how big the impact on the functionality of the application under test is. Classification levels are defined as under:

Defect priority

• High: If the priority of defect is set to be high, it means defect is needed to be fixed immediately. It shows that core functionality fails or test execution is completely blocked.
• Medium: If the priority is set to be medium then it means fix the defect soon. It shows that important functionality fails but we don’t need to test it right now and we have a workaround.
• Low: If the priority of defect is set to be low then it means don’t fix this defect before the high and medium defects are fixed but don’t forget this defect.

Defect priority indicates the impact on the test team or test planning. If the defect blocks or greatly slows down test execution, you might want to select the highest grade for the defect priority.

Defect severity

• Critical: If the severity status is defined as critical then it means a core functionality returns completely invalid results or doesn’t work at all.
• Important: If the severity status is defined as important then it means this defect has impact on basic functionality.
• Useful: If the severity status is defined as useful then it means there is impact on the business, but only in a very few cases.
• Nice to have: If the status of severity is defined as nice to have then it means the impact on the business is minor. Any user interface defect not complicating the functionality often gets this severity grade.

Defect severity indicates the impact on the business of the client. If important functionality is blocked or if that functionality functions incorrectly, the test engineer mostly selects the highest defect severity.

It is clear that priority and severity qualifiers may differ which is depending on companies or projects but basically their value remains the same. It is depending on test engineer that how to assign defect priority and severity after measuring impact of each defect. Nevertheless he should always decide with care as the defect resolution time depends on this.

Severity basically means the degree of impact a bug or defect has on the functionality of the said application or software. Higher severity of the bug means the higher its potential to affect the working of an application in a negative manner. Mostly, the Quality Assurance Engineer determines the severity of a bug.

What Exactly is Meant by Priority in Simple Terms

Priority is nothing but the order in which the said bugs or defects need to be addressed to. Higher priority of a bug means that it needs urgent attention regardless of its severity. Consider this - A bug might be of low severity but if assigned a high priority, then it has to be fixed more sooner than a bug with a higher severity.

Categorization of Types of Severity and Priority

SEVERITY

Critical : This kind of bug or defect is the one which is leading towards complete shutdown of the process that means a tester is not able to proceed further while doing his work.

Major : It is as serious as the critical one, but the only difference is that in this kind of defect certain parts of the system still works while the whole system collapses.

Medium : Some expected behaviour can be detected while running the application but still the application is functional. However, the app will not respond as per the expectations.

Low : It is a minor bug which affects the system and the functionality to an extent which does not hampers its functionality but impacts negatively in regard to the reputation of the web or mobile application in question. It’s not going to result in the breakdown of the system.

PRIORITY

High : High priority means that the defect should be resolved as soon as possible as it's affecting the system severely and has made the system come to a complete shutdown.

Medium : It requires for the defect to be resolved as soon as you get time to address the concerned bug while the application development is also been carried out simultaneously. However, it does not allow developers to sit back and relax if this level of fault has occurred.

Low : There is not an urgent requirement of fixing these kind of bugs. However, it does not mean that you are free to let them be, as it's not affecting the system in a critical manner. It only gives you the luxury to fix these kind of errors whenever you get time after fixing the major ones.

Let’s Make It Simpler With The Help of These Practical Examples

High Severity Low Priority

Logo of the Company : Suppose, a company’s logo colour is showing different or there has been an incorrect spelling of the company’s name in the URL found of what it should be.That means it’s a case of high severity because the company’s reputation and accessibility has been affected in a severe manner. Why Severe ? Because, if the company URL is incorrect, that means, whenever people will type the URL in their browser’s address bar, the site will not open. Likewise, colour fault in the logo can create dissimilarities of the site’s appearance at different places on the web which leads to negative impact on the reputation of the site.

High Severity High Priority

Submit Button on the Login Page not working or not getting Displayed : You may have easily understood about why it's high on both severity and priority. If one is unable to login on your site, then what’s the use of your site and added is the bad response it will generate among the users that will eventually make users leave your site promptly.

Low Severity High Priority

Kick Start not working in a Bike but Self Start Does : High Priority because Self Start could stop to work at any time as self start is more prone to defects than the manual Kick Start. Low Severity because self start is still working and your bike is still functional.

Low Severity Low Priority

A Few Spelling Mistakes In the Text of Home Screen : Both severity and priority are low because it’s not affecting much the functionality of the site and the spellings can be corrected any time with a lot of ease in the free time.

Hope this blog has cleared all the confusions and misconceptions with regard to the ever confusing topic - “Difference between Severity and Priority”.

severity= seriusness

Priority=Demand

Priority and Severity Examples

Can some one give the best example for the following scenario's
1. High Priority and high severity
2. High Priority and low severity
3. High severity and low priority
4. low severity and low priority

Those concept use for defect tracking and resolution:

severity-vs-priority-testing

Both Severity and Priority are attributes of a defect and should be provided in the bug report. This information is used to determine how quickly a bug should be fixed.

Severity of a defect is related to how severe a bug is. Usually the severity is defined in terms of financial loss, damage to environment, company’s reputation and loss of life.

Priority of a defect is related to how quickly a bug should be fixed and deployed to live servers. When a defect is of high severity, most likely it will also have a high priority. Likewise, a low severity defect will normally have a low priority as well.

Although it is recommended to provide both Severity and Priority when submitting a defect report, many companies will use just one, normally priority.

In the bug report, Severity and Priority are normally filled in by the person writing the bug report, but should be reviewed by the whole team.

High Severity – High Priority bug

This is when major path through the application is broken, for example, on an eCommerce website, every customers get error message on the booking form and cannot place orders, or the product page throws a Error 500 response.

High Severity – Low Priority bug

This happens when the bug causes major problems, but it only happens in very rare conditions or situations, for example, customers who use very old browsers cannot continue with their purchase of a product. Because the number of customers with very old browsers is very low, it is not a high priority to fix the issue.

High Priority – Low Severity bug

This could happen when, for example, the logo or name of the company is not displayed on the website. It is important to fix the issue as soon as possible, although it may not cause a lot of damage.

Low Priority – Low Severity bug

For cases where the bug doesn’t cause disaster and only affects very small number of customers, both Severity and Priority are assigned low, for example, the privacy policy page take a long time to load. Not many people view the privacy policy page and slow loading doesn’t affect the customers much.

The above are just examples. It is the team who should decide the Severity and Priority for each bug.

What is Severity?

Bug/Defect severity can be defined as the impact of the bug on the application. It can be Critical, Major or Minor. In simple words, how much effect will be there on the system because of a particular defect

What are the types of Severity?

Severity can be categorized into three types:

As mentioned above the type of severity are categorized as Critical, Major, and Minor

Let’s see how can we segregate a bug into these types:

Critical: 

A critical severity issue is an issue where a large piece of functionality or major system component is completely broken and there is no workaround to move further.
For example, Due to a bug in one module, we cannot test the other modules because that blocker bug has blocked the other modules. Bugs which affects the customers business are considered as critical

Major:

A major severity issue is an issue where a large piece of functionality or major system component is completely broken and there is a workaround to move further.

Minor:

A minor severity issue is an issue that imposes some loss of functionality, but for which there is an acceptable & easily reproducible workaround.

For example, font family or font size or color or spelling issue

Trivial:

A trivial severity defect is a defect which is related to the enhancement of the system

What is Priority?

Defect priority can be defined as an impact of the bug on the customers business. Main focus on how soon the defect should be fixed. It gives the order in which a defect should be resolved. Developers decide which defect they should take up next based on the priority. It can be High, Medium or Low.

Most of the times the priority status is set based on the customer requirement.

What are the types of Priority?

Priority can be categorized into three types:

As mentioned above the type of severity are categorized as High, Medium, and Low

Let’s see how can we segregate a bug into these types:

High:

A high priority issue is an issue which has a high impact on the customers business or an issue which affects the system severely and the system cannot be used until the issue was fixed. These kinds of issues must be fixed immediately. Most of the cases as per the user perspective, the priority of the issue is set to high priority even though the severity of the issue is minor.

Medium:

Issues which can be released in the next build comes under medium priority. Such issues can be resolved along with other development activities.

Low:

An issue which has no impact on the customer business comes under low priority.

Some important scenarios which are asked in the interviews on Severity and Priority:

High Priority & High Severity:

A critical issue where a large piece of functionality or major system component is completely broken.
For example,
1. Submit button is not working on a login page and customers are unable to login to the application
2. On a bank website, an error message pops up when a customer clicks on transfer money button.
3. Application throws an error 500 response when a user tries to do some action.
500 Status Codes:
The server has problems in processing the request and these are mainly server errors and not with the request.

These kinds of showstoppers come under High Priority and High Severity.
There won’t be any workaround and the user can’t do the further process.

Low Priority & High Severity:

An issue which won’t affects customers business but it has a big impact in terms of functionality.
For example,
1. Crash in some functionality which is going to deliver after couple of releases
2. There is a crash in an application whenever a user enters 4 digits in the age field which accepts max 3 digits.

High Priority & Low Severity:

A minor issue that imposes some loss of functionality, but for which there is an acceptable & easily reproducible workaround. Testing can proceed without interruption but it affects customers reputation.

For example,
1. Spelling mistake of a company name on the homepage
2. Company logo or tagline issues

It is important to fix the issue as soon as possible, although it may not cause a lot of damage.

Low Priority & Low Severity:

A minor issue that imposes some loss of functionality, but for which there is an acceptable & easily reproducible workaround. Testing can proceed without interruption.
For example,
1. FAQ page takes a long time to load.
2. Font family or font size or color or spelling issue in the application or reports (Spelling mistake of company name on the home page won’t come under this Low Priority and Low
Severity)

These kinds of issues won’t bother the customers much.

Some more points:

1.  The development team takes up the high priority defects first rather than of high severity.

2.  Generally, severity is assigned by Tester / Test Lead & priority is assigned by Developer/Team Lead/Project Lead.

Final Words:

The above are just examples. Selection of severity and priority may vary depends on project and organization. In Gmail, composing an email is main functionality, whereas composing an email feature in a banking (email option to send emails internally) application is not the main functionality.