> Carrying balances is a positive thing if you pay on time every month.
It improves your score, for sure. Your credit score is an assessment of your value as a customer. A customer who pays off their balance every month before incurring any interest is lower value than a customer who runs a balance and makes payments. The bank wants more people like that.
What impacts your score (in this axis) is utilization of revolving credit: credit used over credit available. Driving the numerator to zero will increase your credit score. Increasing the denominator will also increase your credit score. There is no situation where—all else being equal—increasing the numerator will increase your credit score.
> Your credit score is an assessment of your value as a customer.
No, your credit score is an assessment of your trustworthiness to a creditor, and the expectation that you will pay off any balances in full. Individuals with high credit scores are not generally directly valuable customers as they carry little revolving debt and are given low interest rates for mortgages and car loans. They accrue and use significant amounts of credit card rewards, which further cut into your profits. However, they (generally) make more and larger purchases so you make more money on merchant fees than you do with other cohorts.
It improves your score, for sure. Your credit score is an assessment of your value as a customer. A customer who pays off their balance every month before incurring any interest is lower value than a customer who runs a balance and makes payments. The bank wants more people like that.