What is the difference between the priority and severity of a bug?

Priority and Severity are different characteristics of a bug that help manage the process of fixing it.

• Severity reflects the impact of the defect on the system's or user's operation. It is determined technically and shows how critical the bug is from a functionality perspective.

  • For example:
    • Critical: the system crashes, data is lost
    • High: a function does not work, but there are workarounds
    • Medium: the bug causes inconvenience but is not critical
    • Low: cosmetic errors

• Priority indicates how urgently the bug should be fixed from a business or customer perspective. It depends on business goals, deadlines, and impact on users.

  • For example:
    • High: the bug needs to be fixed in the next release
    • Medium: the fix is planned for the future
    • Low: the fix is not urgent

Example: a bug with critical severity (e.g., application crash) may have low priority if it occurs in a rarely used feature, while a bug with low severity (e.g., typo) may have high priority if it affects the company's image.

Thus, severity is a technical assessment of impact, and priority is a business assessment of urgency.