I don't think this is even true. Lots of people get rich on luck, i.e., inheritance or other connections to wealthy people, or else they happened to come into s

I don't think this is even true. Lots of people get rich on luck, i.e., inheritance or other connections to wealthy people, or else they happened to come into stock (e.g., employed at a startup) that beat the odds significantly. Of course, one has to spend less than he earns to stay rich, but even that doesn't demand scrutinizing one's expenses--one could simply be content or conservative or minimalist.