Merck Engineer interview questions

Basic behavioral questions. I thought the interview went pretty well, no idea why I was rejected. They did not even give any proper reasoning/feedback as to why I was rejected despite following up. Possibilities of favoritism that they could’ve gone with another candidate.

Multiple interviewers, pretty laid back, no lunch, brief tour, asked a lot of hypotheticals, everyone there seemed to like there job or at least the benefits, a lot of overtime available if you wanted