That huge box of extra-large rubbers can be a big ego boost for people shopping for themselves or a flattering gesture for people buying them for a partner. But there are three big problems with using condoms that are too big, especially when they're too wide. Ever worn a pair of shoes that's just a shade too big and suffered the consequences later? Then you already know one of them – friction. Fortunately, blisters aren't the problem here, but condoms can break when there's too much friction. Since they don't fit as snugly, too-big condoms can also leak. And, worst of all, a condom that's too loose may come off completely during sex. Then, the whole scenario moves from protected to unprotected – and possibly very awkward and uncomfortable – in one fell swoop.
Latex condoms are stretchy and should fit snugly, so, while it's fine to comparison shop for a favorite, in most cases, standard sizes do the job.