GPs comment was hyperbole, but it holds true for most countries.

I live in Germany and make a pretty good salary as a developer. If I could, I'd take ½-1 year off work to develop one of a few games I've been designing over the last couple of years. In-between jobs I always start working on them, and those 1-2 months are a blast, much more fun than regular work.

But even though I have enough savings to do so, I really can't, because it would mean:

1. My career progression will pause, less future income
2. I need my savings for unforeseen emergencies
3. Losing out on a year of income will worsen my chances of ever affording my own apartment/house, and will worsen my private retirement savings

When the result is most likely making 0€, it's hard to justify the risk.