Relatively poor selection of certain genres, for example JRPGs and platformers. This usually gets overcome by ports, though as Pike said there's a tendency for PC ports to be a bit shoddy, and can also be overcome by emulation.

PC is the only platform where people seem willing to release completely broken games. Not with some bugs or something, but flat out broken, do not do what they're supposed to.

Several large PC publishers have a massive hardon for insane DRM systems, because they seem to think that inconveniencing paying customers will encourage pirates to become paying customers.