I think you misunderstand the comment, it is a reference to how mortgages work in the US (I know not in most other countries). You can keep ratcheting your int

I think you misunderstand the comment, it is a reference to how mortgages work in the US (I know not in most other countries). You can keep ratcheting your interest rate down over the years, but it will never go up. When interest rates rise, you sit tight. When they drop, you keep refinancing.