Hi Bob,
It's Jim at CompanyX. Hiring is complicated and needs many people to agree on a particular candidate. Often, we don't. Unfortunately, we couldn't all come to agree on hiring you. It's no reflection on you as a candidate and maybe only a reflection on our skills as interviewers and recruiters. We thank you for your time and wish you all the best. Certainly feel free to apply again, and many of us here, including me, may have been bad hires who will be fired soon.
This is very good but just a different way of saying what coffeemug suggested, i.e. no details except that "we don't want to hire you" (as opposed to meric's idea of giving specifics.)
I also think the generic approach is best; in my experience also, giving specifics can open up a can of worms.
Hi Bob, It's Jim at CompanyX. Hiring is complicated and needs many people to agree on a particular candidate. Often, we don't. Unfortunately, we couldn't all come to agree on hiring you. It's no reflection on you as a candidate and maybe only a reflection on our skills as interviewers and recruiters. We thank you for your time and wish you all the best. Certainly feel free to apply again, and many of us here, including me, may have been bad hires who will be fired soon.
Cheers, Jim