What did you change?

The fundamentality of cost is a means to manage scarcity. If something is running thin, meaning there is less of a thing than those who wish to have that thing, then cost must rise such that enough people lose interest in having that thing (i.e. it becomes unaffordable), yielding to those who still do want the thing.

The addition of 'unaffordable' changes nothing. It is already encoded in the original statement.