Why does he think he needs to work 70+ hour work weeks? He mentioned he couldn't sleep knowing user adoption was low. I think the biggest problem here is that he felt pressured to over work himself to solve a highly visible problem.
This affects many engineers including myself. In many cases over working is not necessary and there are diminishing returns, possibly even less overall net returns if you burn out or become too sleep deprived and stressed to function efficiently the following days. In this case he quit, which is an example of this.
As engineers we have to learn how to manage expectations and disconnect from work. As engineering leaders we need to foster a culture of maintaining good work life balance. As founder and CEO, he's in the best possible position to do this. Especially in this case where there is no external deadline.
The thing is - in startups, there always is an external deadline (assuming you're not cash flow positive or profitable) - it is tied directly to your runway and when you'd run out of cash. That is the ultimate deadline for pretty much all startups.
The very early stages of a startup (and even later stages) usually require this much effort because you honestly don't have enough money to last you the "right" amount of time you need - and therefore you need to put in more time.
As you said - this isn't sustainable long-term - but, especially in the early stages, you may not have a "long-term" in that venture if you're not able to put these hours in.
Not to say it's impossible to find a great work-life balance for an early stage startup - but it's highly unlikely.
This affects many engineers including myself. In many cases over working is not necessary and there are diminishing returns, possibly even less overall net returns if you burn out or become too sleep deprived and stressed to function efficiently the following days. In this case he quit, which is an example of this.
As engineers we have to learn how to manage expectations and disconnect from work. As engineering leaders we need to foster a culture of maintaining good work life balance. As founder and CEO, he's in the best possible position to do this. Especially in this case where there is no external deadline.