What Craig said.
Ideally, you're basically comparing a course to every other course out there. Until you've played a lot of courses, you're limited by what you've seen. I have to include myself in that.
I didn't feel knew enough to write an objective review until I'd played 30 or so courses. Even then, my basis for comparison was limited, because I'd only played what was in my area and maybe a bit beyond that. When you've played a dozen or so courses in your area, its pretty easy to see the best of those as a 4.0 or better... because, relative to what you've seen/played, it is great... or at least feels that way.
But is it really that great?
It wasn't till I started getting around MI and the surrounding states, that I realized:"Hudson Mills is pretty good... but maybe it ain't quite a 4.0." In fact, now that I've seen a bit more, perhaps I've been a tad generous with some of my local courses.":\
Now that I've seen more, I don't think there's a course in Metro Detroit area that's better than a 3.5 except for: Addison Oaks (4.0) , Kensington Green (3.75) and Toboggan (5.0). We have many good to very good courses, but those are the only ones I feel are really worth travelling to play.