[vidarh]

Because nobody else would put up with it in sufficient numbers, and then spend ages discussing it in places equivalent to HN afterwards.

It would make it impossible for them to hire. A large segment of potential tech hires salivates at the prospect of being hired by Google as some sort of intelligence test or proof of their self worth, and the convoluted hiring process serves to reinforce that impression. While it puts some people off, it draws others in.

For higher level management positions, marketing and other types of roles, Google does not have nearly the same draw. And for higher level positions the pool of potential candidates is much smaller too.