"17. People rely mainly on their parents for advice on what to do about education, and that has to be among the worst places to go for educational advice" This one certainly hits me hard. With a mother who dropped out of university and a father who didn't go myself and my sister both have good degrees (she's a newly qualified Vet and I'm a startup's birth and death out of uni), and nowhere to get decent advice. I kno…
The important stuff I learned before graduating my bachelors was things like:
1) It's better to be a small fish in the big pond (my career councillor told me this when I was 16, I think I disagreed with it in my first 3 years of uni but now I can totally agree.)
2) You don't owe anyone anything and you aren't tied to anyplace on earth (Mum - grew up moving a lot so when I had an opportunity to attend a more prestigious university my mum gave me a lot of support)
3) Always swap jobs every few years (my uncle worked for the same company for 18 years before being laid off - he has done well but nearly everyone he started working with are execs now)
Most related to your comment is something I was told a few years after university where I was pushing work to fast track my professional development as much as possible. A senior manager told me there is only so much other people can teach you, in the end you need to do the time and build the experience.