In many cases enjoyment and positive judgment go hand in hand. But enjoyment and positive evaluation can come apart in a number of ways. Some works of art do not seem to be designed to be enjoyed. Consider works of art that might be characterized as ‘difficult’ (e.g., some paintings of horrific scenes, certain movies about tragic events, novels that investigate evil, some contemporary political art, works of music such as Threnody for the Victims of Hiroshima). It seems perfectly plausible that in some such cases we may judge these works to be valuable while not enjoying our interaction with them. There are, after all, a whole range of activities and experiences that we may judge to have value irrespective of whether they provide enjoyment (e.g., voting, helping those in need, writing lecture notes, etc.). Another sort of case stems from the possibility that we may be incapable--for some personal reason--from enjoying a work of art that we judge to be good. We all experience such blocks sometimes. Well, I do. I’m tired at the opera, or the play reminds me too much of something I’d rather not think about, or the music was written by someone I don’t like, or the novel is just too darn difficult for me given my limited powers of concentration these days. And so on. I might judge the opera/play/song/novel as good, but I just can’t enjoy it. Things can pull apart in the other direction too. A person may enjoy some works of art that he or she doesn’t judge to be of much worth. One way this can happen is if we recognize that our enjoyment depends on some idiosyncratic feature of our relationship to the work of art. I might enjoy a movie because it is about the toughest philosopher in the world (or about philosophy graduate student vampires) but recognize that this isn’t really a reasonable basis for judging the movie to have much value.
That being said, it seems to me that the fact that we enjoy a work of art is often one of the most important reasons that we judge it to be good. And it’s not unreasonable to take the fact that you enjoy something to be at least some reason to think that it is good. Moreover, we often enjoy what we take to be good—that is, we enjoy it because it is (judged to be) good. So the two notions are not completely unrelated.