Every lender has had the conversation. A borrower comes in motivated, financially responsible and ready to buy, yet the credit score doesn't support the loan. Not because they've managed money poorly, but because the model used to evaluate them was never designed to capture how they actually live their financial lives.
For decades, the mortgage industry operated on a simple assumption that when it came to credit scoring, there was FICO, and there was everything else. Lenders built their systems around it. The GSEs required it. Mortgage insurance companies priced to it. The model was stable, familiar and, for most of the industry, unquestioned. That assumption is changing, fast.