I would agree with NPR that this is the madness of subjective evals. It seems often, that who they like is the most important part of the eval. You can have a weak knowledge base, show up close to rounds, not have much interest in patients but get along well with shooting the BS with residents and end up with honors.
Sometimes this is overt, and sometimes you can't tell. Like being told for one month 'you are going and excellent job!' by everyone on the team. Ask for what you can do to be improving on and they say 'nothing, you are really doing great!' Be told that you did a good job, when you pass in the eval form. Be told that they liked you and they will write good comments for you. And then, after you leave your eval (written by someone else) says that you are bone average and your comments are very weak.
In medicine you are not really allowed to challenge a grade - for fear of making people angry. It doesn't seem like this is a good system for really training people, and for helping them on to the next step since your whole grade can come from someone's incomprehensible comments and eval. And, from whether they 'liked' you or not. That is very different from whether you are clinically sound and progressing well.
I genuine do not understand why a student would be told you are doing an excellent job! nothing to improve and then barely pass the rotation and receive very weak comments. That to me seems very hostile and passive aggressive. The subjectiveness of clinical grades can make you dizzy, but it also seems very unfair sometimes.
In the end, you can chose how you want to behave during these years. Be yourself and work hard, smile and have a good attitude and hope for the best, or try the resident schmooze - which may or may not work for you. These are hard years, and I don't know that I have the answers.