What is an example of when a very expensive, specially made button would be a need instead of a want for a design?

If the design has many layers or complex threading.

Explanation:

In most designs, we would assume that a specially made button that is very expensive would be a want. This is because fancy buttons generally perform the same jobs as regular buttons. However, an example of when this is not the case would be if a particular design has many different layers or very complex threading. In this case, the button might become a necessity, as it might work better than any other button.