People can always choose to use the product, use an alternative, or use nothing at all. In fact, not using your product is their default state of being, and you’re trying to get them to do something different and effortful in using your product. Adoption requires a baseline of user involvement in order to overcome inertia.
It’s easier to facilitate people doing something that they want to do than it is to convince them to do something they don’t want to do. It’s easier to enhance their desire for something they already wanted than to instill a new desire. It's easier to meet people where they are than it is to ask them to do something that is too challenging. This is why it's crucial to design for Goal Resonance and Difficulty Matching. We need to Intentionally design for failure states because if user involvement is voluntary, then we want people to try again when they fail rather than get discouraged and switch to alternate behaviors.
This points towards the necessity of using Behavioral Product Strategy.
It’s not enough for products to be usable, finding the person’s positive motivation to use an app is crucial. As I explain in Habits are the wrong thing to focus on for most behaviorally designed applications, deliberate action is required at all stages. People need to willingly exert effort to use an app well. Ethical Behavioral Product Strategy asks what behaviors are necessary for user success according to the user's own definition of success, and how the company can sustainably increase the likelihood of those behaviors.
Like many of the claims on this website, it may be best to Think of this claim as a parameter rather than a claim of universal truth. For example, Cody Morrow of Minerva School described his own online product for teachers and students. The teachers and institutions are the ones who purchase their software. Students of Minerva School are end users that don't have a choice over whether they use it or not. Sometimes teachers in institutions that made the purchasing decision simply have to use it.
So how would you design for people who use a product simply because higher up decision makers said it should be so? I'm still thinking through this. However, I will say that if end users are unsatisfied, even if they don't have direct decision making powers, they might still make a stink. There might just be a longer timescale to switch to something new than in the B2C space I primarily work in where the user has viable if sub-optimal alternatives.