I used to never wash a quilt before giving it because I didn't want it to look used. But then I came to this site and learned it is best to wash them so they are ready to use. No one wants to find out the quilt they made had a seam split or fabric failed in another way after giving the quilt.
I always pre-wash my fabric - especially flannel. Once I bought the perfect blue flannel, it was set to be the back of a quilt and when I washed it the first time it was awful. Never had I seen flannel do what it did. It pilled, it was misshapen, the the color faded in spots. I should have taken it back, but I couldn't find the receipt and it had been a while since it was bought.