Why are some ot us so dam moody? Could it be there's a useful benefit to all those swinging mood changes?

Or are the moody among us just attention seekers, how about those who have the same mood all the time are they even aliveWhy are some ot us so dam moody? Could it be there's a useful benefit to all those swinging mood changes?
Hormones can cause mood swings e.g. PMT/PMS, and they can be caused by poor impulse control that can be either learned (spoiled brat syndrome) or the result of frontal lobe damage e.g. Phineas Gage.



Can it be useful? Perhaps attention seekers might make good entertainers, but if you want to be a professional you need to control your mood i.e. the show must go on whether you feel like it or not.