[brwr]

+1 for "Would you be afraid to hire your smartest friends".

It's also worth considering whether you would help find your replacement. If not wanting to invite your friends is a bad sign, what does it say if you wouldn't tell people you don't even know to work for the company?

[AndrewSB]

I mean if you're not willing to find your replacement, I think the answer is pretty obvious...

[brwr]

Maybe. There are other reasons you might not want to help find your replacement. Maybe you are more junior than the company needs and you don't feel comfortable interviewing someone more senior than yourself. Or maybe you've never interviewed anyone before, and don't feel comfortable for that reason.

Very few things are obvious, when you think about them.