It typically required more direct sources of trust. If you were a grocery store, you might let customers you personally knew to be good for it, run up a 'tab' and settle on payday. If you were a bank, you might only lend to rich high-class people. You can find this all around the world today; the US is a standout for credit scoring and for access to credit. When a British person wants to sell their house, it has to happen on the same day that the buyer sells their old house, and the house they're moving into to be sold, and so on in a big same-day daisy-chain, until you hit someone who has enough cash for initial outlay. In Japan, up until very recently, you could expect your boss to need to co-sign your apartment lease (and your landlord to immediately escalate any disagreements to your boss).

Poor people couldn't borrow and middle-class people paid really high interest rates. Credit ratings are pretty much what enabled the expansion of availability to everyone.