If a design gets screwed up because of wrong color or poor stitch quality and it will take you a long time to remedy the problem by removing stitches you have to ask yourself: Is it worth it? If it’s a t-shirt or some low-cost polo shirt then let it go. Spending more more than an hour or two is not worth it for something that costs a couple of dollars. Unless of course there is absolutely nothing else to do in the day then go ahead.