According to the trigger help, the improvement trigger will send an email "... any time there is an improvement. A build is considered to have improved wheneverit has fewer failures than the previous build." When a build improves all the way to having 0 test failures, this trigger is not triggered. I looked at the code and the ImprovementTrigger is using number of current failures > 0 (numCurrFailures > 0) as part of the criteria if the trigger should run.
However, this condition matches the help text. Can the code be fixed? Or, the help text could be changed, but I'd prefer fixing the code so that this trigger produces the similar "back to stable" email messages. Thanks.
EDIT: I see that there is a "Fixed" trigger, so maybe just tweak the help text?