"I enjoy making games more than playing games, and I suspect most professional designers feel the same way. In fact, for kids who say 'I want to be a game designer when I grow up,' this distinction is key for telling the real future designers from the wannabes. The ones who really want to be a designer are spending their spare time making games, not just playing them. The ones who still think that designers just come up with an idea - 'Let's make a game like Castlevania, but with lasers!' - and then go back to playing games full-time, are the ones who just play a lot and don't know the first thing about design." - Ian Schreiber, independent game designer and Adjunct Professor at Columbus State Community College
If I may add my own thought to this sidebar, it requires a lot of self discipline though. I reckon that once you started the work, you can go on, keep working, go to sleep when people wake up, and end up tweaking your design and prototyped systems for hours. But getting this started is the most difficult part. Being independant is not easy. When you're working within a group, it's much easier to follow the flow, there's some emulation, a self support. But when you're alone, either at home or in a hotel, during the weekend, it's very hard to switch your computer on and start working, even if you actually enjoy what you do... otherwise, you wouldn't even think about doing it at all.
It's even harder when all the elements of a normal life in society require time to be dealt with.
Besides, there are many good games which
need to be tried, at least. Even when making games, you should try new ones, and even force yourself, and even spend several hours on some of them to understand certain aspects relative to details which a superficial approach would miss. But this is not easy either, because of time restraints.