Earlier quoted context omitted.
That's one reason we rely heavily on thorough, structured reference checks.
How do you structure your reference checks? And what do you do for new hires who are very early in their careers and don't have real work references? Also, I'll note that three of the above employees were sourced via referral from either other employees or friends of execs.
I'll echo the sibling post for inexperienced candidates. References from jobs in other careers also work. But to be honest, if someone can't find anyone to speak in-depth about their achievements and teamwork, they are going to have a really tough time passing the bar to get hired. We don't generally do work samples of any kind, but I'd probably have to make an exception in that case, to get some kind of picture for how they work.
We've certainly had a couple people not work out on our engineering team. But I don't think we've ever hired a total dud or a toxic person.
It's interesting that you mention internal referrals, because I think that can be a major source of bias. People feel obligated to put in a good word for their friend, and if I hold the referrer in high personal regard, my natural skepticism of them as a reference diminishes. I feel referrers should say their (small) piece at the beginning, but from that point onward, the hiring process needs to be independent of their influence.