Underestimation of game development.
Go look and see how games are built, before you get a team setup for failure.
Writing a game require a lot of good script writers, a lot of good artists, and to top it off, a lot of fucking time(No exaggeration), and even that's not enough sometimes.
Do some research first, because the moment you said "I don't know much code" instantly proves that you have done little to no research, but rather threw a idea that pop up in your head; because if you don't know much "code", then you will literally understand nothing to how a game is developed.
Not being a dick, just being straightforward.