Originally Posted by Nerevarine 
I disagree - I think that RPG developers (even indies) can and should add content that the player might not see. It adds a purpose to the exploration - even if that exploration is within a level - and encourages replays. The key is to only add "optional" content that is reasonable in scope. This might include a hidden path here, an extra piece of loot there, perhaps an extra side-quest… My point is that these such things don't take that much time to implement - so long as a developer doesn't go completely overboard - and it makes the entire experience much better than a purely linear one.
And that is probably the reason why 95% of indie games that are started are never finished. They should focus on the core game.