Take this yarn for example. Grass is a worsted weight, cotton/hemp blend. Great for Arkansas summer. But what does it want to be?
Before the advent of Ravelry and Patternfish, yarn shops relied on the yarn manufactures to provide pattern support for their products or the yarn shop's owner or employees own creativity. And let me tell you that not all yarn companies had good pattern support.
Appear stage left - Ravelry and voila, you can search thousands of patterns that call for a summery, worsted weight yarn.
Let's do a little experiment, shall we? I searched Ravelry for Grass and clicked on the Pattern Ideas tab. And 9 pages of pattern ideas came up. That's 54 patterns. Everything from hats, dishcloths, and baby items to sweaters, lacy shawls, and market bags. The possibilities are endless.
So fall in love with a yarn and then search for what it wants to be.