Except how much someone is willing to pay for something depends on, among other things, prevailing market prices, which are influenced by marginal costs.

I may be happy to buy a house for anything less than 200k but if all houses are selling for 100k, then that (or something like it) will be the amount I am actually willing to pay.

If construction costs rise and now builders are only selling houses for 150k, I will now be willing to pay that price.