So I know eventually my ass will get fired. It's just a matter of when.
I don't really understand it. But it's how the industry works.
Edit: 8-12 is for unambiguously great attorneys. A lot of decent attorneys get shown the door after 4-6 years. People who can't hack it (usually because they won't put up with be worked like a slave) will only make it 2-4 years. A lot of people quit.
The downside is the average experience of your employee is going to be a lot lower, but that must not be the top goal of the law firms that employee this.