It's not how bonds work because you can't pay off a bond early other than by buying it on the open market at the prevailing price.

And furthermore, not all loans are fixed-rate. UK mortgage rates are relative to the Bank of England base rate.

>you can't pay off a bond early

Only assuming it doesn't have a call provision.

Some variable rate mortgages in the UK are. You can also get fixed rate.

Fixed-rate mortgages are offered in the UK, but they are only fixed at a good rate for a short period of time (maybe 2-5 years) before they go up to an unreasonable rate, which would force you to renegotiate the mortgage to get the new prevailing rate at that time.

So it's effectively a variable rate anyway.

Well, a series of shorter term fixed rates. Which I guess makes it variable over the entire lifetime of the mortgage, but a bit more predictable than a true variable rate.

You can get 10 year fixes, but they are of course more expensive than shorter term fixes.