I imagine it is because many of us have had it happened. We worked hard and did what we are supposed to do and now have to suffer because of another person’s mistake. A mistake that they are shielded from. It isn’t like the upper management is going to get fired because they overhired.
Additionally it tends to come in waves and that seems to be more based on what they think they can get away with not based on what the market is actually doing. One of my main vendors just did that to their engineering department. They are publically traded and their financials are fine.