Not everyone likes the mentoring and pedagogy aspects as much, and that's fine IMHO. I do like it despite turnover and "wasting" resources on some people, but I'm coming from an education/instruction background. I can see how some profiles would not be really interested in doing that.
The GP said they didn't like it but did it anyway. They stopped because the developers they mentored would leave when they got good. My point is that it's better from them individually to mentor someone and have them leave because it builds their network.
