I assume that the fellas at Valve had prior experience someplace before making HL1 yet the maps were levels below what eventually was released after the the games release.
Yes I entirely agree, but don't with what you think is the reason behind this (the lack of feedback from the community they previously had access to.)
As ReNo stated, there are totally different pressures while working for a games developer. If the publisher wants something in a particular way, you've gotta do it no matter how stupid you think it is. If the publisher wants it done by "yesterday", that's when you've gotta hand over the assets no matter if you personally think it's done to the best of your ability or not. If the publisher wants twice as many levels yet aren't willing to hire more guys to get the job done sufficiently well enough, you've just gotta get on with it and make do as best you can. If the publisher insists on framerate being maintained on lower spec PCs you've gotta strip out the fancy details, while people making levels in their own spare time can freely choose whether to set the spec requirements higher for his level and make the rooms not as 'boxy'. Etc etc.
Sure, getting in outside people to critique would help, but it's much more due to lack of time and resources and publisher pressure than the reason you're suggesting. Delaying a game by a few months to take into account critiques likely costs $100,000+ per month - a publisher simply isn't going to stump up this sort of extra cash per month. Yet delaying a user-made level by a few months just means people are playing the beta version of a level for a while longer.
When creating user-made levels you're in complete control of what you create, how many levels you do, when you're happy they're finished, and you have access to relatively "finished" technology. You seem to be thinking that there is some sort of Utopia for game development in all professional companies, that people get all the time, resources and technology they need, and it's the lack of feedback which is the problem, when it's usually anything but. Only those developers like Valve who hit the big time with a game selling millions of copies get to do what they want and set their own schedules.






