Uber doesn't disclose their exact process, of course, but it appears to be mostly stack ranking. Firing the bottom 10% or whatever ends up meaning around a 4.6

Uber doesn't disclose their exact process, of course, but it appears to be mostly stack ranking. Firing the bottom 10% or whatever ends up meaning around a 4.6 in most markets, but median driver ratings vary by market. The stack rank isn't immediate either, and may have factors such as number of trips driven. But that's basically what's going on. (I don't know specifically how this applies to UberPool ratings)