You left out the most important factor of all: content. Imagine a game with the best graphics, music, story, and gameplay. It's over after 1 hour. Now the game is really disappointing. On the other hand if you have a super long game without much variety then that gets old too. Content is actually what people are looking for when they buy a game, both quantity and quality of content.
(You also left out challenge, but content is even more important.)