Lilian U. The list of why hired people don't "work out" is miles long.
On paper, as we know, is BS.
People can fluff their way in interviews, especially when interviewing people who are not good at interviewing prospects.
Interviewer bias is HUGE.
Looks are deceiving, but they get hired over capability.
Ideally sales people should not be interviewing sales people. have your tech people interview them. They smell BS miles away.
Vice versa, have sales interview tech people, in addition to their tech interview. This helps understand their team/personality dynamic.