[neonfreon]

I don't think "would hang out with them outside of work" or "would make a good lunch mate" is the right way to think about personality fit when hiring. I've had many effective coworkers and employees that I didn't spend any time with outside of work. If you can't work with someone that doesn't click perfectly with you, shame on you, not them.

'That's the kind of person you don't want to hire to work on a PHP app.' Definitely. I would also be surprised if they were even technically capable of giving a good answer, given that attitude.

'You also don't want an arrogant know-it-all on your team, even if he is a genius with code.' Agreed. And since nobody else wants to work with someone like this, this type has a tendency either tone down their attitude or to get weeded out before they can really grow technical expertise. I've interviewed hundreds of people and can only think of a couple of examples that were close to that, and those were either for internships or people fresh out of college. Do you often run into people that are technically a great fit but are too arrogant to hire?