Assume that one is searching for some permanent research positions. I am a bit curious what does an employer wants to see in recommendations letters.
Obviously, recommendations have nothing to do with scientific achievements. For that, they can check the publication lists. As I can imagine, the purposes of recommendation letters could be:
demonstration that the applicant can socialize normally with other people
they want to see recommendations from high-profile people, since these demonstrate that the applicant has established enough connections and potentials for influence in the community
they want to see recommendations from the applicant's current boss, since it demonstrates that the applicant has worked hard and loyally for his/her current employer
they want to see recommendations from people who they want to collaborate with, such that hiring the applicant would help with social connections
(from xLeitix) they would like to see the community's view about the applicant's work -- which means anyone in the community qualifies as a referee.
Are these valid purposes for recommendation letters, and what else am I missing here?