Once a company reaches a certain size, being able to micro manage individual workloads to max efficiency become impossible and individual middle managers have an incentive to appear like their whole workforce is necessary.

They’re not intentionally throwing money away because to them, the appearance of growth has to come before actually growth. They consider useless hires the cost of doing business. And when it fails, “they can just make the though decisions” and do the layoff the shareholders want. Otherwise, how to do explain the waves of mass hirings and mass firings?

https://en.wikipedia.org/wiki/Bullshit_Jobs

anthropologist David Graeber that postulates the existence of meaningless jobs which cause psychological harm. He contends that over half of societal work is pointless and becomes psychologically destructive (when paired with a work ethic that associates work with self-worth) because workers are required to pretend their role is not as pointless or harmful as they know it to be.

They do do that with fake job listings.

A lot of jobs are pure bullshit jobs that only exist because the corporation needed to hire inorder to appear growing. They then do mass firings to appear like they’re cutting costs. It’s all smoke and mirrors for the shareholders.