All cash, all the time
I switched my personal finances to all cash, whenever possible, about 8 years ago. Yes, in this connected society I have a debit card with no balance that is used exclusively for on-line transactions, and is funded as needed.
I have more discretionary money now than I EVER had when I lived on credit/debit cards. I never carried any consumer debt, I just never seemed to have spending money. I have been able to pay off major debt - car, house, etc, and am now 100% debt free.
I don't know what it is. Maybe it is the 'having to give up a tangible thing' to get something that helps control personal spending (vs. swipe & get). Either way, it is one of the best decisions I have ever made. No way I will go to a 'cashless' society. I'll barter with hard currency (gold & silver) first.