If i only have 3 subscription levels I am selling to customers, how do I use potentials?

I don't understand how potentials work for a saas business like ours. I don't want to have an open text field that i have to type a new potential name in every time I am working through a deal when I only have 3 subscription levels I am selling to all customers. Can someone help me understand how to configure potentials for this type of scenario?

I guess this question is relevant outside of the context of subscription too - what are some examples of how other companies are using the "potential name" field for instance? If a company is only selling 1 widget, are they writing in "widget 1" as the "potential name" each time they are setting up the record?

Thanks!