The one thing I got from my parents ( they both graduated high school at the start of the Great Depression, my dad in 1929, was to avoid debt. They considered it almost evil.
The only serious debt I have had in my life was my mortgage, which I double up on paying off. Credit cards get paid off monthly. The only time I carried consumer debt was early when I used a couple of installment plans to build credit instead of buying outright.
It's a very unusual year if I pay $100 in interest, total.
I'll buy a car this year. I'll pay cash for it, and make payments to the bank account until it's "paid off."
And the thing I see so many young people doing today is the plastic mistake. Buy everything with a piece of plastic, including lunch and latte every day. That's always shocked me. Spend a measly $10 daily for lunch and a latte, and you're going to spend over $2,000 a year. And yet the fact that it's done daily means that somehow it's ok. So people who would never frivolously spend $2k do it nonetheless and aren't even aware of it.
The little things add up so quickly.
Combine that with the horror of Bay Area rents and living costs, and it's too easy to go into increasing debt, like my friends in Piedmont with the $1.5 million house who owe $60k in credit card debt. And can't seem to get out from under.