Bargain Queen Meg has a post about why fashion trends matter. She talks about the difference between making trends work for you and being a fashion victim, noting that top fashion industry people are not themselves slaves to trends.
One way to make trends work for you and to keep your wardrobe from looking outdated is to pay attention to details. For example, look at how the shape of women’s t-shirts has changed over the last two decades:
Notice how tees have gotten tighter since the 80’s. Sleeves have also gotten tighter and shorter as shirt length has gone up then back down again. This is one reason I buy a couple new, inexpensive t-shirts at Target twice a year. They’re always the right shape and the right colors, and they’re both practical and inexpensive.