I think game developers often don't understand why their game doesn't become a success. And like now they blame piracy, but fail to see that using the same logic all games of that era should never have sold as much as they did. In fact more popular games should have more piracy problems and less popular should have sold more in proportion.
When commercial Rogue was still a new game I was a young player in 80's. Rogue would have been simply too complex for me. We the younger generation (I guess the huge majority of players back then) liked much simpler games: shooters, platformers, etc. In fact Ultima IV was the game that got me interested about RPGs and I was at that time 15 or 16 years old. It had easier UI and gameplay, an important thing to remember still today when trying to create games for wider audience. The older I get the less I play -other- than roguelikes so it's some kind of age issue as well, at least from my perspective.
Games that were good in commercial way also sold well and made some game developers millionaires. It's worth remembering to balance all that piracy talk.