3 ideas
The real value of accumulated wealth is the ability to walk away from any job, boss, or situation that you find intolerable. Once you have it, it changes how you negotiate and what you put up with. On this view, money is worth more as leverage over your own time and choices than as a way to buy luxury, so each dollar spent on consumption is a dollar taken out of your independence.
The stock market always goes up over the long run, but it does so through regular, severe crashes that no one can predict or time. Investors lose money by panicking and selling during those drops. Success therefore depends on behavior more than skill: you commit in advance to holding through declines, and you treat a crash as an expected event instead of an emergency.
Hold nearly everything in a single low-cost total-stock-market index fund while you are working and adding money, because stocks give the highest long-run return and your ongoing contributions absorb the volatility. Once you stop earning and start living off the portfolio, add bonds to smooth the ride. From that point, spending about 4% per year keeps the portfolio likely to outlast you.