I'd say attitude and personality are greater predictors of success than technical competency for very senior level people too. I can't think of many people who reach senior levels with poor attitude and personality. And those that do often hit a wall. Eventually, their attitude and personality gets in the way of their brilliance and other people's willingness to work with them.

I think it doesn't matter only in cases where you were the guy who started it all or you're some crazy skilled mercenary for hire brought in only for emergencies. You can treat people like crap for as much as you want if you're in control like that. Maybe it's even necessary for those unicorn situations. And yet, even Linus Torvalds has said that he needed to change.

Finally, I'd say poor attitude and personality lends itself to arrogance, which also makes technical people hit a wall because their arrogance decreases their technical curiosity. Improving one's skill really does require a certain intellectual humility.

> I'd say attitude and personality are greater predictors of success than technical competency for very senior level people too.

Yeah I’d agree. But I think somebody with a good attitude, who can get on well with others, has a greater chance of being able to quickly fill in any competency gaps they have in non-senior positions. For senior positions, the baseline is higher. I’d hire somebody with good character, but inadequate competency (within reason) for a lower IC position, but for a senior position, I’d want both.