[strlen]

> A person can do 10 or 20 interviews and have none of them (even the ones who seemed good) get an offer.

That's actually fairly common in the Silicon Valley. It's 10 to 20 people on the market, not 10 to 20 programmers selected at random: some are specialists in fields other than the ones you're looking for (or their resume is misread by the recruiter e.g., someone who has experience with enterprise search but is being interviewed for a web search position), others lack certain specific knowledge you do want, yet others are looking for a place where they can be "promoted to their level of incompetence".

A rate of 1/10 or 1/20 (5-10%) is actually very good and indicates an ability to recruit and screen well.

[smackfu]

If 10 or 20 people are getting to the technical interview stage and failing to qualify, that points to a problem. That adds up to a lot of non-productive time for the interviewers.

[nostrademons]

If you reject those 10-20 people at the phone screen stage, you end up with another problem that Google has been accused of: you overlook many qualified candidates who just had a bad day on their phone screen or drew a bad interviewer or got quizzed on questions that aren't their specialty.

It's a balancing act. Reject too many in phone screens, and you miss out on talent. Reject them at the interview stage, and you waste interviewer time. Accept them and put them on teams, and you drag down the level of the team and cause morale problems. Google's been accused of all of them, but in my experience, hiring sucks wherever you are, and they do the best they can given the data available.