I have one gingham winter shirt now and two plaid. I'll be wearing them again this year, but in a slightly different way, perhaps, than last year -- I'll try to think of ways to freshen them up a bit, different combos than last year. (Maybe with my so-far nonexistent cropped pants or culottes, for instance, LOL.)
And I feel a bit different than Lisa about this. A shirt (or 3) is to my mind, an excellent way to play with a trend and freshen a closet. So what if you only wear it for a season and then move on to the next pattern? It's not too pricey. And if it is not truly "dated" then you can pass it along to someone else who will be thrilled.
Mind you, I did wear my plaid shirts a lot more than twice each -- I actually wore them a lot throughout their season. So I guess that is the real issue. Only buy a trendy seasonal item if you know you will wear frequently within its season, or get maximum joy per wear.