[laserbeam]

It all depends on how many applicants you get. If you're as big as Google and everyone and their grandmother applies, you can afford to have longer interview rounds for positions where you need to be thorough. Otherwise you spend more effort in bringing people to the interview.

[irrational]

We are a Fortune 100 company that everyone on the planet has heard of. We typically get 500+ applications per position. But we still only do a single hour interview to make a decision.