There is one huge difference between prison and startup - alternatives you have.
When you are in prison all you can have, if you don't try to escape is a miserable life till the end of your days. On the other hand - after ten years of hard work you can get free. It gives you really big motivation - negative motivation is usually greater than positive.
With startup you have choice between pretty good life (if you are a programmer you can find really nice job) and great success. Motivation is rather small comparing to prison situation.
Having said all this - author still is right - you need to have fun from journey, not only from target.
When you are in prison all you can have, if you don't try to escape is a miserable life till the end of your days. On the other hand - after ten years of hard work you can get free. It gives you really big motivation - negative motivation is usually greater than positive.
With startup you have choice between pretty good life (if you are a programmer you can find really nice job) and great success. Motivation is rather small comparing to prison situation.
Having said all this - author still is right - you need to have fun from journey, not only from target.