Agree with what everyone else said. Depends on what I am working on and how far off the seams are. And I try to sew patterns that allow me to measure and trim often.
Like you, I am getting better. But perfection takes too much time/energy, and reworking to attain perfection isn't any fun. So I just try to be as careful and accurate as I can without obsessing about it. After all I do this for enjoyment.