User with only issue view and add note ermission can change issue status
As reported by Lee Hugues in the forum (see), someone which role allows him only for viewing issue and adding note will still be able to change properties status, assignee, % done and target version.
It requires also that a workflow is defined for the role.
#4 Updated by Jean-Philippe Lang about 11 years ago
More a consensus than a particular reason. Changing the status generally means that some work was done on the issue and that progress, assignee... may be changed.
I know that it's not a perfect solution. Would be much better with permissions per attribute.