Kinda, some people I know who did poorly at undergraduate/masters did a lot better at the PhD level though and vice versa as research is very different to being

Kinda, some people I know who did poorly at undergraduate/masters did a lot better at the PhD level though and vice versa as research is very different to being taught. There is such a lack of permanent research positions compared to postdocs and PhD students that I'm not even sure it's selecting for the best people.