I think this is in interesting point (modulo the remark made elsewhere about "assuring" success), but I don't have the evidence to know how it should affect your decisions.
The research I cited found that first time and failed entrepreneurs have a 20% chance of success, whereas "skilled" entrepreneurs have a 30% chance of success. So if you can become "skilled" in one stint of employment, then you would expect to succeed sooner by being employed first than if you were doing startups that whole time.
But it's entirely possible that it takes multiple stints of direct employment to obtain whatever knowledge makes you skilled, in which case your argument is valid. I just don't know of any evidence about this though.
The research I cited found that first time and failed entrepreneurs have a 20% chance of success, whereas "skilled" entrepreneurs have a 30% chance of success. So if you can become "skilled" in one stint of employment, then you would expect to succeed sooner by being employed first than if you were doing startups that whole time.
But it's entirely possible that it takes multiple stints of direct employment to obtain whatever knowledge makes you skilled, in which case your argument is valid. I just don't know of any evidence about this though.