How to set Severity and Priority for a bug?

How to set Severity and Priority for a bug?

Severity and Priority, these are often a confused concepts and are almost used interchangeably amongst not only test teams but also development teams. There’s a fine line between the two and it’s important to understand that there are indeed differences between the two.

Severity: Severity determines the defect’s effect on the application. Severity is given by Testers.
“Severity” defined as – The degree of something undesirable, something hard to endure, extreme plainness. Severity of a defect/bug tells us how undesirable the defect is. For example, a bug that causes the program to crash and terminate would be considered as high severity, while a minor spelling error might be of low severity.

Priority: Determines the defect urgency of repair.Priority is given by Test lead or project manager.              “Priority” as – Status established in order of importance or urgency. Priority of a defect/bug tells us how soon it is required to fix the problem. Priority reflects a business decision as to how soon that bug should be fixed. Priority of the bug determines what gets fixed next and what does not. The priority of a bug can be decided from either the Project management point of view or from the user’s point of view.


Priority:Define defect priority value by level of urgency to be resolved for the defect.

Priority 1 – Critical (P1):This generally occurs in cases when an entire functionality is blocked and no testing can proceed as a result of this
Priority 2 – High (P2):defects must be resolved in this release.
Priority 3 – Medium (P3):defects would like to be fix, but won’t hold shipment for them.
Priority 4 – Low (P4):defects are not as strong as desirable.

Severity:Define defect severity value by impact of a bug.
Critical / Show Stopper (S1):Crash, loss of data, corruption of data, severe memory leak Prevents developers or testers from performing their jobs. Impacts the development process.An error which causes a program or system interrupt, or which causes program execution to abort. System personnel refer to this type of error as a “show stopper”. This error has the highest severity rating.
Major or Severe (S2):Major loss of function, as specified in the product requirements for this release, or existing in the current
Moderate/ Normal (S3):Non-major loss of function. 
Low or Minor (S4):Issue that can be viewed as trivial (e.g. cosmetic, UI, easily documented)or an enhancement.
Bugs that can be raised based on above category combinations like for example:

1). High Priority and Major severity

1.1) The application does not opening the home page after login

1.2) The application crashes whenever a person attempts to submit valid input on the registration page.

2). High Priority and low severity
2.1) The spell mistakes that happens on the cover page or heading or title of an application.
3). Major severity and low priority
3.1) 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.

3.2) An application crashes after multiple use of the functionality (For Ex. “Save” button use 200 times then that application will crash.)

4). low severity and low priority
4.1) Any cosmetic or spell issues which is with in a paragraph or in the report (Not on cover page, heading, title).

What is Software Testing? Why is software testing necessary?

What is Software Testing?

Nowadays, Software testing plays an important role,which helps to improve the quality, reliability and performance of the software applications. Usually software testing is considered as one phase of the software development life cycle (SDLC).

Software testing is the process in which the defects are identified, isolated and subjected for rectification to ensure that the product/project is defect free in order to provide quality to the product/project, hence customer satisfaction.

It includes, a set of activities conducted with the intent of finding defects in software so that it could be corrected before the product is released to the end users.

Why is software testing necessary?

⇒ Software testing is really required to point out the defects  that were made during the development phases, because it can be very expensive in the future or in the later stages of the development.

⇒ It’s essential since it make sure of the Customer’s reliability and their satisfaction in the application.

⇒It is very important to ensure the Quality of the product. Quality product delivered to the customers helps in gaining their confidence.

⇒Testing is required for an effective performance of software application or product.

If the Product released to the market without conducting proper testing then,Software that does not work as expected can have a large impact on an organization. It can lead to many problems including:
⇒ Loss of money : This can include losing customers right through to financial penalties for non-compliance to legal requirements
Loss of time : It will take much time to resolve
Damage to business reputation : If an organization is unable to provide service to their customers due to software problems then the customers will lose confidence or faith in this organization

Software bugs can potentially cause monetary and human loss, history is full of such examples

⇒ The China Airlines Airbus A300 crashing due to a software bug on April 26, 1994 killing 264 innocent lives.
⇒ In April of 1999 ,a software bug caused the failure of a $1.2 billion military satellite launch, the costliest accident in history.
⇒ In May of 1996, a software bug caused the bank accounts of 823 customers of a major U.S. bank to be credited with 920 million US dollars.

⇒ Mariner Bugs Out (1962):Cost: $18.5 million

⇒ Hartford Coliseum Collapse (1978)
Cost: $70 million, plus another $20 million damage to the local economy

⇒ Medical Machine Kills (1985)
Cost: Three people dead, three people critically injured

As you can see, testing is important because software bugs could be expensive or even dangerous.