>games aren't supposed to be appealing to most of the players
I'm assuming you don't exactly mean that. A game with no appeal is a failure. The creator would not be able to express their point as the player would not be able to see through such flaws. If their impression is that the game is bad, the won't play/finish the game. Even if they do play it through, many players will be left with only the thoughts of the flaws, not the creator's meaning. Without appeal, the point means nothing.
Also, to clarify, I don't mean the player's should necessarily dictate what the game should be. What I mean is that the player can be a guide in the same way an editor may be. An editor doesn't normally stray away from the author's main point, but rather helps them better express their point, along with making that point more appealing to the reader (grammar and spell checker aren't their only jobs). Often, the editor asks the author to rewrite segments, even the whole book, or to rethink parts of the story, but the author still can freely express themselves. Thus, the author gets their point out with confidence others will listen, and the reader gets a better experience. It works the same way with games, as the player is the "reader"- a critic, consumer, and in the instance of in-progress games, a possible editor.
Beginners rarely will produce something good; even experts will need lots of editing to produce something worthwhile. If the people are available, why wait for these "editors" to help until the final product? A good game can still be produced, with the creator's point, and the creator can learn from it. While others have their input, the creator still has their final say.
I will admit, however, that their are times when these people should be ignored. 'Cause we all know how adding guns to a Sonic game came out.
And finally, a question for you and other creators: If a game is meant to be a unique expression of a creator's ideas, why are all of the games on /fg/ clones of Yume Nikki's gameplay? (Food for thought, there may be favorable answers)