Credit and debt are like meth. If you only use it once in awhile when you need a boost - like a military pilot in a war flying three sorties a day or a really loooong mission in-flight for 18 hours or more, it's fine.
Butt for 98 (or whatever) percent of people, and corporations are really just people who make decisions, debt. credit, and meth are gonna lead to addiction and really badd prollems and ~OUTTcomes.
I have inculcated in DaSun at least a couple of core things to keep his mind on: (1) avoid debt and credit cards (unless you ruthlessly (ok, that may be a bit strong - how about assiduously?) pay off the balance each month and avoid finance charges), and (2) be extremely selective and marry the right woman who has the right values that match yours.
In my 'spearients, those are the two main things that lead people to unhappiness if they screw up either of those things - and the two things usually go together.
If one can focus on those two items, and avoid crass materialism, I think one can have a basically happy life. Of course other things happen beyond our control, butt if you can avoid debt and have a stable relationship whatever your taste in that area, you're giving yourself a good chance of a life with general happiness and contentment.
And remember, in the Bigg Scheme of Thangs, NONE of this matters. Don't sweat the small stuph, and it's pretty much ALL small stuph.