In my early 20s, I was earning $120K a year while living in rural Texas. I had an expensive apartment (3 bedroom), a leased Lexus IS, and spent lavishly. I also got a second car (a Honda Fit) for grocery store runs. If this sounds absurd, yeah I know.
2 years of this and I had some 401K savings but no after tax investments. I wasn’t even maxing out the company match. Just before each pay day, I might have had $800 in my checking account on a good day.
My case might be extreme (I don’t know), but it was certainly poor financial decisions.