This is on the flip side of what I usually cover on the Career Search side of things, but it talks a little bit about Google's philosophy when hiring new employees.
- New hires have to be better than the mean of the existing employees (so that the mean is always increasing or at least staying level, this is hard to do if you don't have a good means of generating statistical data on existing employees and candidates)
- An interesting aside, good people want to work with good people and bringing in someone who isn't at par can effect the existing workforce.
- Hiring manager shouldn't be responsible for choosing the candidate because they will almost always rather have someone than no one. Google takes the approach of finding good people first then finding projects they will fit in to once they have been hired.
Official Google Research Blog: Hiring: The Lake Wobegon Strategy