Switching to cash-only spending is beneficial in several ways:
The first is the limitation it puts on you on what you buy. If you don't have a credit card, you will only purchase items that you can afford at a particular time.
Consumers can protect their credit and avoid unneeded debt by paying with cash.
When you pay with the cash you've budgeted for purchases, it's easier to track exactly how you're spending your money. It's also an eye-opener and keeps you in the reality of how much cash is going vs. coming in.