It's already been pointed out that a bad DM can make a mess of any campaign, regardless of whether they start by making an adventure or start with a setting. If we lived in a world where books of generic encounters and books on adventure building outsold settings, would we say "adventure building is bad" if there were DMs running crappy railroaded adventures? I'd certainly hope not.
But, the question that should be asked is why do setting books outsell adventure building books? Or at least, I find that question interesting. Why do we see reams and reams of setting material, far in excess of what you could possibly need and vastly more than adventure material?
Is it because having setting material makes your life as a DM easier? I don't think so really. You can have all the setting guides in the world, but, you still have to sit down and do the work of crafting adventures. Or, could it be that setting guides sell so well because people spend far more time on the easy stuff of daydreaming campaigns than the hard stuff of actually making them?
In the end, you're right Darth Shoju, it doesn't hurt anything usually, to world build. Just as having desert doesn't hurt anything. Although, apparently, there are those here who think that you cannot possibly run a campaign without world building. That crafting a campaign based on adventures rather than setting will result in lockstep railroads or completely bland and flavourless experiences. So, I would say that the world building paradigm has managed to really burrow itself deep into gamer psyche.
Sorry, got off on a tangent.
I was saying that you're right. At the end of the day, so long as the campaign gets made, who cares? My point isn't that world building is bad. I've admitted that. World building isn't bad in the sense of, if you do it, you're doing something wrong. What I'm calling for here is a shift in thinking from the style of Forgotten Realms (and frankly the majority of settings out there) to the style of Freeport or the Adventure Paths.
For me, I'd MUCH rather have twenty or thirty thousand pages of adventure paths, or campaign in a box, than 20000 pages of Forgotten Realms material.
For the homebrewer, just starting a new campaign, perhaps the common wisdom of top down or bottom up isn't the best advice. Maybe. Just maybe. Perhaps, a better approach is to go straight to the work of crafting adventures and then paper over the cracks as needed.
Hey, it doesn't always work either. Look at Dragonlance. There's a campaign setting that saw its genesis in modules. Lockstep modules. But, you could also look at some of the other setting modules, like Cauldron, or Savage Tide, or World's Largest Dungeon, which, while perhaps railroady in places, certainly aren't locking the players to the rails. For the homebrewer, who doesn't have to worry about page count and budgets, he can craft a whole web of adventures, or matrix to use Rounser's word, and then go back and add any scenery that's needed.
When you do world building first, you have to go through and do all that work of crafting the world, which, if you do a good job of it, is a pretty work intensive thing to do. Once you have, say, Fargoth, THEN you have to go back and start making adventures.
My point is to turn it around. Do the adventures first. That way you can save yourself a whole pile of work doing the world building. Heck, if you want, you can simply raid Dungeon magazine, the WOTC site, and various other companies out there and come up with a couple of dozen (or more) interwoven adventures without having to do a lot of work. Then you go back and spackle the walls.
See, if you go the other way, and buy setting material like FR, you're likely not going to use the majority of it in your campaign. You just wind up with so much on the cutting room floor. But modules, you can pick and choose based on a theme. You wind up with a lot less extra.
IMO. Of course.