Anecdotal evidence isn’t evidence, but I’ve seen enough people say things that align with my own experiences to think that it at least isn’t a fluke. I used to pay off my credit card expenses same day or same week and my credit score was in the 640-660 range and would fluctuate widely and often. It’s been only two years since my first credit card and my only other current accounts are my student loans. I now regularly carry a balance month to month, but always make the minimum payment and pay off the cards within 3 months to stay on top of it. I started that during the pandemic when I had a ton of unexpected expenses. My credit score has since shot up to 765 and my credit limit has quadrupled in the past two months when I used to previously get denied for limit increases when I was making more “immediate” repayments. It’s hard not to at least speculate that the system is based on how much interest profit you generate for someone else.