You get the behavior you incentivize. In the “early days”, design docs were a tool to agree on a direction and provide context to your coworkers about what you’re doing. Later, as new people joined at an exponential rate, they were told by well meaning managers to write the docs for perf reasons, and things kind of spiraled from there. Google’s culture became a cargo cult of itself.

Some companies I worked at after Google were reluctant to discuss their promotion process in detail, because they saw what happens when people microoptimize for it.