In Notches case, that guy needed much more than just well running code. I don't know details about his success story, but either he, or one of his co-founders needed some art, marketing and game design skills, or MineCraft wouldn't have grown as large as it is today.
I don't think this is true. Minecraft succeeded despite not having art, marketing or game design skills. It's clearly programmer art, and anyone who has played survival mode for any length of time can tell that there is little to no intelligent design in the gameplay. It's a sandbox, period. It also exploded virally through the player base. Not through some clever marketing strategy that Mojang put together. Basically the stars aligned for Minecraft and it was successful despite anything Mojang was actually doing to the game.