I never heard of deliberately building a stash. I thought it just happened. In my garment making days I just bought the yardage indicated on the pattern. I learned not too long after starting to quilt to take three yards if I like it. I still have some I bought ten or twelve years ago. I love going through it and dreaming how to use it. Sometimes it's too pretty to cut up. I have drawers full of ufos that I'm going to devote 2011 to. Then I will get to dive into the big pieces in the stash. Then there is the trunk full of scraps. I'm afraid that collecting fabric is a vice shared by many quilters.