Spot on, rvn1045. Your brain will be bent into the wrong shape, your engineering and product management skills will have become too specialised, you won't realise what you took for granted in the workplace until it isn't there, and then you'll have to split your time between your start-up, your new partner, and your new children, with less than half the income and no security.

Nevertheless, some people will do it better at 29 than at 22, and others will excel at another age. We're all different.

When the time comes for you, if it ever does, you'll know.