I choose to drink beers I believe, in advance, are good. I skip those that I think I won’t enjoy, unless the situation forces me to try one. If I one day run out of "interesting" beers to try, then I will consider changing my habits. For now, though, I go for quality over quantity.
My beer ratings are not reliable. The environment surrounding me, my mood, the amount of sleep I got the night before, the food I had earlier; all of these, and many more, affect my ratings in ways I cannot always take into account in when tasting the beer. I might have enjoyed a beer once upon a time, only to be disappointed by it later. Or vice versa.
When I rate beers, I try to keep it simple. Very rarely do I notice some very specific aroma or flavor. However, I try (at least in my private tasting notes) to describe, as accurately as possible, the level of enjoyment a specific beer brought me. This, to me, is most important.