Your definition of "not-lazy" by it's very nature relies on systematically working overtime.
Investigating and fixing flaky tests is either explicitly covered by a ticket, and thus a part of run-of-the-mill tasks, or something a developer does in unscheduled tasks by going above-and-beyond including in work hours.
Finding a bug, creating a ticket, and working on it is not proof of non-laziness as that's a part of the basic job description.
Refactoring a feature is either tracked by a ticket and covered in normal ticket-assignment processes, thus not a demonstration of lack of laziness, or it's something you do in your own time.
You have to clarify where you find the time to do all that "above-and-beyond" stuff because it's either normal work done on normal company time, which surely doing the normal/bare minimum is not proof of not being lazy, or it's going the extra mile, which is certainly not done during normal office hours.