interaction design - Do numeric steppers have an affordance problem?

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This is a relatively common control. In addition to pressing the up/down buttons, these steppers typically support additional input methods:

1. typing the desired number;


2. long pressing the buttons which allow the numbers to run;


3. and sometimes using the keyboard arrows in place of the buttons.

Recently I discovered that a very experienced and technical user, with 20 years of experience in software development, wasn't aware of all these additional methods. He believed that the only method available to get to the right number was pressing the buttons i.e. to keep clicking until you reach it. He wasn't aware of the type, or long press controls. I can see how the design of the control might give that impression.

Can we rely on users knowing how to use numeric steppers? Is it common for users to experience this kind of difficulties with the stepper?