I never liked the idea of dividing life into segments since you can't really quantify or rather classify the circumstances. Libertarians are praising the idea of equal opportunity and reject the idea of equal outcome. I personally reject both conceptually. No one will ever or can ever have an equal opportunity because our opportunities don't necessarily mean they are all good. In practice, an opportunity is often choosing the lesser evil and in many cases that's a decision that will follow you throughout your life and will have life-long side effects. I've had to take difficult decisions and even though I undeniably took the right ones, I understand that some of those completely derailed some aspects of my life and I've accepted it. Some of those had to happen pretty early on to no fault of my own mind you, but to me, realizing that some things are outside your control and you have to accept reality, even if you hate it, is the day you become an adult. Of course, there are people who face no consequences no matter what they do and they die of old age with the mindset of a 4 year old. Especially if they were raised to be egomaniacal, self-obsessed, spoiled brats, of which there are a lot.

This may be an unpopular opinion but everyone needs to face a critical mass of unfortunate events at some part of their life. The earlier it happens the easier it is down the road.