Earlier quoted context omitted.
Along those lines, one of the things that I still struggle with after 20+ years of working, is squaring this feeling of not working enough/earn enough money to have a comfortable retirement, while at the same time trying to live my life and not just work myself until death (very original, I know). So I've always had this conflict with the saying that goes something like "nobody regrets not working more, while in thei…
Few people regret not working more. Almost everyone regrets not having achieved more.
For what it's worth, working more would build a habit of doing so. A good work ethic would mean that you need a bit less motivation or discipline to get things done, due to it basically being just something you do.
It doesn't have to be just for some corporation, but also when you're trying to build some personal project, especially the ones that might get a bit bigger (writing your own blog engine or static site generator, maybe even a game engine, or planting crops or building a shed for all I care). Sometimes there won't be many shortcuts to success, but just boring slog of legwork that needs to be done.
In that regard, I definitely regret not working more, because I still need to rely on motivation, which is fleeting, or discipline, which is unpleasant, all just to get through things sometimes, even when I take care of myself in every other way (sleep schedule, nutrition, activities, mental health).
As for the whole retirement aspect, sadly I don't have answers for that, the state of the economy is concerning sometimes.