sometimes i do ... sometimes i don't.
how's that for a clear, concise, helpful answer?
:lol:
seriously, though, i usually backstich at the join-points of y-seams. i will also backstitch if i'm not sewing all the way to the edge of the fabric.
otherwise, i usually don't backstitch. i do, however, keep my eyes peeled for seams that have "come undone" at the ends. (sometimes, the growing weight of the top, in combination with all the mandhandling, pulls the ends apart.) when i see those, i add some reinforcing stitches before i add the next patch, block, or row. if i don't, i'll have to hunt for those spots later to fix with a hand-needle and thread.