I think of chatbots as asking the question "what if we could put an AGI (artificial general intelligence) in here" and programming the closest approximation for the task. Sometimes that's a natural language interface, and that's what most people focus on (lots of money in customer support and sales automation). But if our office coffee machine had an AGI I wouldn't care about natural language comprehension, I want to be able to tell it to have coffee ready when I come to the office early and I want it to convince humans to clean it.