Why are some bots great and others meh?

Bots are no longer FAQ answering machines
I was spending a lazy afternoon looking for fitness apps I could download to restart my fitness journey. Typical of Google store, you see hundreds of them everywhere. I chanced upon a fitness company which was eye-opening. A gym that functions entirely online with a chatbot as an interface.
Not only did the chatbot took in my personal details, but also provided a plan for the weeks to come, connected me to a real personal trainer for accountability and p