Because its easier to throw more people at projects, than sort out lower performers.

When theres a want to reduce head count, then they can go look at lower performers and drop them.

This happened at an apartment I was in. It ends up that water was making its way behind the panels and eventually rotted away the drywall and wood framing. It took the maintenance crew 3 days to repair it all because there was nothing behind the panels.

I was told they had to do a similar repair to the bottom 2 units as water had made its way down the walls.