Hammers are used for pounding things, which is why many people don't realize that hammers make perfectly good doorstops. This lack of creative insight is an example of:

Question

Quizplus · Accepted Answer

Functional fixedness is the tendency to think of an object only in terms of its typical use or function. In this case, people see hammers as tools for pounding, and struggle to see them as anything else, such as a doorstop.

Hammers Are Used for Pounding Things, Which Is Why Many