It's the response of "I don't care about this thing, and I don't care about improving it, so please stop making me waste my attention on the thing I don't care

It's the response of "I don't care about this thing, and I don't care about improving it, so please stop making me waste my attention on the thing I don't care about." In many people nowadays the scarce resource is not time or even money, but attention; and not every aspect in your life is worth your attention to try and improve it, that's premature optimization, wasting effort on improving something that ultimately is insignificant.