It's like giving birth, isn't it. You spend all that time and energy and money creating this unique thing that has never existed before. Then you launch it into the world, where you're forced to learn to let it survive, or not, on it's own merits. And that's hard to do.
But then you start finding yourself being interested in the possibilities presenting themselves to you by doing it all again. And soon the last one has been forgotten and the next one has become your new life's obsession.
It's curse, really.
It's definitely a labor of love, that's for sure.