Saying “coincidence” is basically claiming there is no reason for an observed pattern. This is really more of a last resort when considering explanations for certain patterns, because it’s probably the weakest claim someone can make.
Generally, patterns are not coincidence because if an outcome is truly a result of randomness, then there is an extremely low chance that there would be a pattern.
Also, 12 is not the whole data set. The whole data set should include the people who weren’t hired during the hiring process. This is unknown to us.