Now, what do things like “good”, “mediocre” and “bad” mean? Subjectively, whether the reviewer feels the story is successfully told. Things like special effects, directing, acting, and the like might come into play, but the reviewer is a writer first and foremost, despite the near constant spelling/grammatical gaffes, and that’s where his knowledge lies. More often than not the writing will be what is judged.
Also note that just because the reviewer loves a film doesn’t mean it gets recommended. His tastes are his tastes. And sometimes those tastes are… odd.
Reasonable disagreement is something the reviewer appreciates, but please realize that odds are good he will not change scores based on such debate. Also please realize that he reserves the right to change his stance when he feel like it. Which may or may not have a good reason for happening.