Are we talking about the same thing?

The point of the terminal level rule is that there is a point, bellow which you are not actually contributing all that much more in output then it takes to supervise and mentor you. At some point you need to be clearly net positive. This generally means you can mostly operate on your own.

If it becomes clear you won't make it to that level, then something is wrong. Either you are not capable, or not willing to make the effort, or something else. Regardless, you get forced out.