While there are 3 levels of approval, it's not exactly as crazy as it sounds at first glance.
After your phone interview with an engineer, you go in for your on site interview and talk to at least 4 people, both managers and engineers. They each write up their impressions of you without discussion between them. They pass their impressions on to a hiring board that reviews those, your resume, and what positions are open.
That board passes the recommendation onto a final board who I suspect is largely a financial gatekeeper, just to approve stock grants and controls company-wide hiring rates and company wide strategy.
After your phone interview with an engineer, you go in for your on site interview and talk to at least 4 people, both managers and engineers. They each write up their impressions of you without discussion between them. They pass their impressions on to a hiring board that reviews those, your resume, and what positions are open.
That board passes the recommendation onto a final board who I suspect is largely a financial gatekeeper, just to approve stock grants and controls company-wide hiring rates and company wide strategy.