My thoughts, based on a few startups I've observed among my friends: once a startup gets to 2-3 full-time founders, the probability that it will fail because people aren't working hard enough goes near zero. The company might fail for other reasons, but once you have 2 or 3 dedicated, full-time founders, "lack of effort" is not even on the list of the top 20 things that can kill it. Occasionally, an individual person might drop below acceptable effort levels-- that person usually leaves for a more stable job in a month or two. It just doesn't make sense to work for a startup if you're going to put in a half-hearted effort, so the less committed people usually leave before they become a problem.<p>What I said above is untrue for some 1-person startups that are effectively abandoned, and for startups where people stay in their day jobs and therefore really aren't able to contribute enough to get the thing off the ground. But when you have 2 to 4 people working full-time on a startup, there are still a lot of things that can kill it (bad product, poor team dynamics, bad investor relations, just plain bad luck) but a lack of aggregate effort is very, very low on the list.<p>What seems to be far more common are hours- or sacrifice-related squabbles, and these can utterly break a company. Let's say two founders are working 80 hours per week and one is working 50, but they're all about equally valuable and productive. What happens if, when it's time to split equity, the third founder gets a smaller share? Possible fight. Or worse yet, what if he ends up with lower status within the company and is treated more like an employee, because he didn't "pull enough weight"? This is where fatal fractures happen. Nothing goes wrong because there wasn't enough effort, and nobody put in such a low level of effort as to cause problems, but the perception of unequal sacrifice and dedication has spawned a very nasty conflict that is destined, at some point in the future, to create a fight that could damage (or ruin) the company.<p>People tend to think of rules surrounding office hours and vacation allotments as exploitative in nature. They can be, but they're also there, in an odd way, to protect people against certain kinds of social dysfunction. Working from home, for example, is great when you have a good working culture, because people can work more productively and are happier. If the environment's dysfunctional, to have people working from home is going to make it a lot worse, because of the distrust that it will breed. In a dysfunctional work environment, it becomes important (until you've made your exit) to be cautious and show up at "normal" times, because the perception of working hard becomes more important than actually working hard.