Sewing a well executed quilt top is so satisfying. For that to happen, a lot of care must be taken in the preparation and stitching of the quilt pattern. Very small variations in cutting or sewing can end up making large variances in the final product.
I was once asked to help figure out the problem in sewing a high school drama production costume. It just could be made to fit properly or look like it was supposed to. When the participants came to me, the problem became immediately apparent. The pieces were not cut closely enough along the pattern lines. Small deviations in cutting were resulting in the garment not fitting well. The same is even more true, of quilt tops.
A variation of less than a quarter of an inch makes the difference of an entire size in a dress. In garments those difference may only involve two seams. Just imagine the size difference only an eighth of an inch makes over a width of ten or twenty seams common in quilt top piecing. Because there are so many more seams in quilt piecing than on garment sewing, even more care must be taken in the cutting.