Why do so many leaders push to start everything even though we know lower WIP = faster, higher quality and less burnout?

I want to know psychological reasons and evidence as I'm going to attempt to team my portfolio managers and senior leaders about unlocking flow instead of (as well as) managing dependencies.

They have no idea their WIP or the damage it does, and they spend an absurd amount of money on trying to track dependencies (but doing fuck all about them and fuck all about minimisng them)