From Qt Wiki
This is an attempt to make the selection of the 'right' priority of a JIRA issue more transparent.
This is work in progress
The authoritative resource is on Jira - this page should be understood only as a tool.
Start with priority 3. Then raise, or lower the priority based on the bug's severity, visibility, whether it's a regression, or whether there's a workaround.
|Severity||-1||Does the bug make the application unusable (crashes/hangups …)?|
|Regressions||-1||Does the bug break code that worked in (recent) previous versions?|
|Visibility||+1/0/-1||How many people using the feature are affected? Just a few (+1), some (0), quite many (–1)|
|Workaround||+1||Is there an (easy) workaround?|
Other factors that might alter the priority: Compilation issues, legal issues, potential for data loss, etc.