My weekend getaway bag has huge exterior open pockets with just a small snap closure on each of them. I would put small bottles of lotion in them, and they would fall out a few times! Maybe I'm just too fidgety or something, I don't know. Luckily, I only put medium-large items in the main open interior, but that's a lot more secure because of the flap *and* belt to scrunch the top up. I have a lot of open top bags with just a small closure, and I am extra careful with not swinging them around too much for fear of losing my wallet (god forbid) or other items.