Very few owner-occupants voluntarily sell out of a low rate. The lock-in effect is real and durable. When prevailing mortgage rates sit well above the rate a homeowner already holds, selling means giving up cheap financing and replacing it with a far more expensive loan on the next house. Most people simply will not do that without a strong reason, so listings from that group dry up. The sellers who do show up in that environment are selling out of need: - An investor looking to liquidate a position quickly - A probate sale after a parent passes - An older owner relocating across the country to be near family Those are life-driven and finance-driven necessities, a different animal from a homeowner casually trading up and surrendering a low rate to do it. The practical read for a buyer: inventory tends to stay tight whenever current rates sit well above the rates existing owners locked in, because the normal move-up seller stays put. That dynamic is tied to the spread between old and current rates, so it outlasts any single moment in the market. When the spread narrows, more of those discretionary sellers come back.