When lenders size up potential borrowers, they aren't just looking at how much they spend, but where they spend as well. If you've gotten a letter in the mail congratulating you on a freshly-inflated credit limit (or a new cash-back bonus like I did) chances are your lender has noticed you've been diligently paying off your card and selectively shopping where you can afford to.
"For example, if you normally shop at high-end stores and regularly pay off your card, and then suddenly start shopping at discount stores and carrying a balance, the lender could use this behavior data as an indicator that you have become higher risk and could take steps to minimize its exposure," says Nazari. "Alternatively, if your behavior data indicates you are a good risk but you aren't generating a profit, an issuer might determine how to incentivize spending."
How to improve it: Since Behavior Scores are based on triggers like long-term credit card activity, late payments, limit breaches, and fees, if you can figure out how to improve these, you'll be able to beef up your score.