I work at a Big Tech adjacent (or Big Tech, depends on your definition) company and was there pre-IPO and it happens for the reason that varjag described in their sibling comment. What makes it even more idiotic is, as the pre-IPO/lean culture dilutes, more people will use their level to pull rank in meetings, as the level itself becomes more of a target than the work/goals. Then the politics around levels will become ultra-competitive. Google didn't get to their tortuous promo process in a vacuum after all.