Even for job interviews, liability isn't really the reason. As a general principle, conveying true information does not incur liability. In the specific case

Even for job interviews, liability isn't really the reason. As a general principle, conveying true information does not incur liability. In the specific case of job interviews, as long as the feedback is true and not of a legally discriminatory nature, there are no grounds to sue, and such a case would be thrown out by summary judgement. Any employment lawyer would laugh someone out of their office who came to them with a "case" like this. I'm inclined to think it's primarily for the reasons mentioned elsewhere: avoiding back and forth arguments. Frivolous lawsuits from _pro se_ plaintiffs might be a minor consideration, but, as I said, those are easy to get thrown out, provided you're telling the truth and the reason isn't related to any protected classes in employment.