Oh--my biggest is when the fabric gets sucked down into the feed dogs when sewing small pieces together, :evil: or just the ends of larger pieces. It was happening with my new machine--the Quest--but then I remembered it came with a single hole needle plate--so I switched and no more troubles. :D
How much you want to bet when I switch to do a fancy stitch--I forget to change the plate and I break a needle? :roll: