A long time ago, I was a VC/growth equity investor. Reference checks were <i>incredibly</i> important, as a startup's chances of success, are, on average, very much correlated with the strength of the team in a variety of areas.<p>First, obviously, we were looking for red flags. We had ways of phrasing questions designed to get people talking (esp about negatives). Also, more importantly, we were looking for names/contact info of other people who worked with the person we were checking that weren't on the reference list they provided to us. We'd do the same thing with customer references.<p>Second, we didn't know most of the people provided as references. A random stranger's opinion is interesting, but not that useful, especially when phrased in terms of "good/bad" or "exceptional/not exceptional." What was more valuable was to find out what <i>kind</i> of person we were dealing with, which is something that you really can learn from a few random strangers. For example, in past lives, has the CEO been an effective salesperson? Does s/he need a strong COO because s/he tends to let details drop here and there? The line of questioning went something like: "If you were going to build a team around this person, who else would you want on it? What qualities would the other team members have?"<p>In other words, references are just another data point, and I believe their value is not a binary determination of that person's ninja-rockstar-astronaut-whatever-ness, but a more nuanced read on that person's abilities as they contribute to the team overall.