I've been with Amex for 20 years and my Amazon Visa is the next longest with 15-ish years. So, it's not length of credit history, which is one component of a FICO score. It's one of the reasons why I have excellent credit, in addition to making all payments. I've never financed anything on a credit card. I aways use my credit card like a debit card. I do this to get points and rewards. My spending on my Amex card more than pays for the annual fee. The only thing that really attracted me was the 0% for 1 year.