Severity vs priority, settled.
Severity describes the impact of a defect on the system. Priority describes the order in which it gets fixed. They are set separately and often disagree, and that is the whole point.
The difference
| Severity | Priority | |
|---|---|---|
| Question it answers | How badly does it break the product? | How soon must we fix it? |
| Based on | Technical impact on function, data or users | Business need, release timing, customer impact |
| Usually set by | The tester who logs the bug | The product owner or lead, in triage |
| Changes over time? | Rarely, the impact stays the same | Often, as deadlines and plans change |
| Typical levels | Critical, Major, Minor, Trivial | P1 (now), P2 (this release), P3 (later), P4 (backlog) |
The four combinations
| Combination | Example | Why |
|---|---|---|
| High severity, high priority | Payment fails for every user at checkout. | Core flow broken, money lost every minute. |
| High severity, low priority | The app crashes when a report is exported in a format only one internal team uses, once a quarter. | Severe when it happens, but rare and with a workaround. |
| Low severity, high priority | The company name is misspelled on the home page. | Nothing breaks, but every visitor sees it and the brand suffers. |
| Low severity, low priority | A tooltip is two pixels out of line on an old browser. | Cosmetic and seen by almost nobody. |
Severity levels
| Level | Meaning | Example |
|---|---|---|
| Critical | The system or a core flow is down, data is lost, no workaround. | Login fails for all users. |
| Major | An important feature fails; a workaround exists or only some users are hit. | Search returns no results for one category. |
| Minor | A feature misbehaves but is usable. | Sort order is wrong on a secondary list. |
| Trivial | Cosmetic or wording. | Wrong font on a footer link. |
How to say it in an interview
- Severity is impact, priority is urgency. I set severity from what the bug does; the product owner sets priority from what the business needs.
- Give one example of high severity and low priority, and one of low severity and high priority. That shows you understand they are independent.
- Mention that priority can change before a release, while severity usually does not.
Questions
What is the difference between severity and priority?
Severity is how badly a defect affects the system. Priority is how soon it should be fixed. Severity is about impact, priority is about urgency.
Who decides severity and who decides priority?
The tester usually sets severity when logging the bug. The product owner or lead sets priority during triage, based on business needs.
What is an example of high severity and low priority?
A crash in a feature that very few users reach, with a workaround, such as exporting a rarely used report format.
What is an example of low severity and high priority?
A spelling mistake in the company name on the home page. Nothing breaks, but every visitor sees it.
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