What happens if you forget to include a return statement in a function that requires it?

When a function is defined to return a value but the return statement is omitted, the function will complete its execution but will provide an undefined value as its return. This means that when the function is called, the result assigned to that function call will be undefined. Additionally, if the function relies on a value that is expected to be returned for further operations, it may lead to errors when trying to use that undefined value later on.

For example, if a subsequent line of code attempts to manipulate or evaluate the result of that function call, the absence of a valid return value can cause unexpected behaviors or runtime errors. Hence, understanding the importance of the return statement is crucial for ensuring that a function behaves as expected and provides the necessary output for further processing.