Maybe I should have specified, but maturity is a sliding scale. It's not pass-fail. Someone can be immature enough not to take care of the 'unfun' things if they have to do them manually, but be 'mature' enough to delegate them when they can afford it. Someone can be so immature that they don't even bother to delegate it even if they can afford to...

It's also maturity to be able to recognize that your time might be better spent elsewhere rather than demanding that you be the one to do it yourself.