Why are there so many managers who get into these positions with no leadership skills?

honestly this pisses me off so much and i see it happen so often they get into management and leadership positions because why? they are experienced but shouldn't they have managemnt and leadership skills? i got a new manager and he is so so bad. – basic manners non existent – seems to have no empathy – just seems to lack awareness and so on it just boggles my mind how people lke this get into managemnet positions? literally emotional intelligence of a fucking donkey