Flag of Valor

Why is it, when you get to the last block for a quilt it never works out the first time and you have to tear it out not once, but more than once.  This is a quilt kit from Moda called Flag of Valor.  Part of the proceeds goes to Quilts of Valor which presents quilts to wounded veterans.  This can be purchased at http://www.cowgirl-upquilts.com/