I don't know why everyone is assuming that the monk doesn't do as much damage as the fighter. He can potentially do more damage than the fighter, and he has speed and bunch of other cool abilities.
At 4th level, the monk is flurrying and using ki to do THREE attacks with d8 damage and full strength mod. All with no feat investment. If they all hit, that's 3d8+3xSTR. The greatsword wielding fighter on the other hand is doing 2d6 + 1.5xSTR, plus 2 for weapon specialization. Even if you ignore his extra attack from ki(a limited resource), the monk is still doing more damage. And he scales really well. He can do 8 attacks at 16th level! And they all do more base damage than a manufactured weapon does. Yes, he's not going to hit with them all, but he does have full BAB - 2 when flurrying, so he's not really behind the fighter that much.
Monks are great out of the box, but it only gets better for them once you bring in style feats. Dragon Ferocity is silly, and Elemental Fist is a great way to pump up even more damage. There are of course many other options for monks in the supplements, if you want to do things other than dish out damage. Paizo has given them a lot of love there.
Conclusion - Monks are at the very least on par with fighters.