Or the very first time you open the bag, the zip seal pulls away from the rest of the bag.

Or the seal doesn’t line up properly and can’t be zippered no matter what you do.

Or the seal is one of those cheap single layer ones that cross-threads and pops back open every time you think you’ve got it.

Or the zip opening doesn’t cover the whole bag, and you, moron you are, cut the top instead of the disturbing mouth hole they want you to use.

I end up clipping them half the time anyway… good thing large packs of wood clothes pins are still commonly available at the dollar store :)