Which is why, as I said, a good review weights an opinion with a critical argument. But no matter how objective that argument is, the opinion still stands.
I can say that Donkey Kong Country Returns has excellent, creative level design. I can weight this argument by stating the objective fact that nearly every, if not every, stage in the entire game introduces a new mechanic, and/or remixes an old one, in order to keep the stage design fresh and inventive throughout the experience.
The statement is factual, but my personal enjoyment is not. Someone may agree with the introduction of new mechanics with each stage, but for their own reasons not enjoy these mechanics specifically. It is then their job to back-up why they don't with critical analysis.
At the end of the day, neither of us is right or wrong. We both agreed on a point, but left with different experiences due to the wonder of subjectivity.