2) As an indie dev, you're suppose to attack the easiest, lowest hanging fruit to build your income base. After you're past a point, you can take on ambitious long-term projects. Otherwise you are always depending on a "hit" title.
You have to wonder where Notch would've been if he hadn't sold Minecraft before he was "done". As flakey as he (all of us really) can be as a dev (he's admitted as much himself), he definitely needed people depending on him continuing work.