[nostrademons]

The problem there happens when you get a few years in and realize that "the other side" is far from guaranteed, and that there's a good chance that you've spent 16 hours a day, 6 day a week for the past several years working for nothing. Most people do have needs in their lives besides just working, and when you deny those needs for years at a time, eventually it builds up and you quit. The unfortunate part about this is that very frequently it's right before your startup would've succeeded - you can't predict when or whether your startup will succeed, and so you have no idea of knowing whether this hurdle is just the dip before your eventual smashing success or whether it'll be like every other hurdle with no end in sight.

There definitely is something very relaxing about focusing on only one thing, but it only leads to long-term success if you've picked the right thing. I know entrepreneurs that worked for a decade on their companies, and then folded them up without ceremony because they'd poured their life into them and yet they were generating significantly less revenue than a day job would.