Die offizielle DNF-FAQ meint dazu:
1.12 - Why is DNF taking so long?
While this question constantly comes up from concerned fans, the fact is that the game is not taking as long as it may seem. As stated by several 3D Realms employees numerous times, quality games simply take time. What has been taking the most time is all of the optimizations and additions 3D Realms has been making. In the words of George Broussard, "The fact is that we're not massively delayed. Going to Unreal did set us back, but mainly because we refused to be a TC and not advance tech. We added LOD, skeletal animation, motion capture, and tons of other little enhancements to the Unreal engine to make it more interactive. That all takes time."
Level designer Stephen Cole has also commented on this issue: "If DNF was a TC, it would be done by now. Levels, art, models, all are easy and quick to produce. If you want a rehashed TC, that is. If, however, you want something you haven't seen before, it takes time. If you want something that won't be outdated when it comes out, it takes more time."
And also some comments by Joe Siegler: "If we had wanted some quickie piece of crap, it would have been out ages ago. It takes time to innovate - it doesn't take any time to shovel any old crap out there. Since we are not a publically held company, we aren't beholden to the same things that some big companies hold their development teams to, hence we can afford to take the time to make a quality product. Besides, once it's released, no one will care how long it took, they'll care that they have a cool fun game."
1.9 - Why has DNF been in development for over 4 years?
Development on DNF originally started after 3D Realms got the Quake 2 engine in December 1997. Prior to that they experimented with Quake I technology until Quake II tech was available. The Quake I part was not considered actual development on DNF, if anything just R&D on potentially using Quake technology. The reason why they seem to be so late is because they switched engines in the middle of development to the Unreal engine and have added lots of new features to it. This obviously takes its toll on the timeframe. The only thing that remained the same when they made the switch to Unreal tech was the textures, all maps and meshes were redone.
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