For example, if you've failed so many times that your total failure time is around 30 minutes of trying and failing, the retries counter should turn red, or some other indication should appear to remind you to take a break or try a different beatmap, especially when the perfect mod is enabled. Sometimes you can get so engrossed in trying to clear a song that it's 30 minutes later and you can feel your pulse without checking manually. You're no good in that state, and the game should probably tell you to back off for a while as a suggestion.