I'm making a scrappy with blues and neutrals right now. Turns out most of my leftover blues have a royal/bright tone to them and I'd imagined this one being more dark/sedate blue. So I started mixing what I had (since it was supposed to come from leftovers in my stash ie:scrappy) and ended up purchasing more 1/4 yd pieces to cut up for strips, to mix in. As of last night, I was starting to like the look of the mix, but yesterday morning I was thinking I'd end up splitting the blues and making two smaller quilts, one bright and one dark.
This is definitely one of the reasons I have such a big stash. I change my mind on colors as I'm going. I just don't have the ability to envision what all the fabrics will look like when they're cut up and put next to one another. Not a bad problem to have in the big scheme of things though...