I don’t work in Silicon Valley, but I did work for Silicon Valley-based company on a satellite campus on the other coast in an area semi-seriously called “Silicon Alley” in NYC. Personally… I think people like the energy of it all being in one place and a bit of a buzz of energy in the air. It’s sort of like living in an arts district, you see others and you are inspired or driven to compete harder, possibly both.
Plus, this industry (as others have pointed out) is incredibly incestuous, and people like to hop around companies without having to change where they live, friend groups, etc.
Finally, You aren’t going to convince the brightest minds in tech to move to the middle of no where (or have a long commute even from a suburb) to work for a single company that they may or may not like. Having a desirable location is a huge negotiating factor.
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