It's certainly a leading contender. This moment from Jaws 3-D is laughably bad, and sort of the opposite of the beautiful practical effects that distinguished Spielberg's original movie. But is it actually the worst?
Bloody Disgusting makes a pretty strong case that this glass-shattering bit goes beyond embarrassing into some uncharted territory of shame:
This isn't some home video slasher shot in the woods, this is a studio movie! With a real budget! It came out in the 80′s and featured a shot that would have been deemed too shoddy even in 1920. See for yourself. This video isn't slowed down or anything – that's just the choice they made in the movie.
And indeed, you can see for yourself, below: