The greatest benefit I get from use cases is that they focus on the user. Use cases help me to think about what the user wants to do instead of only focusing on implementation details. The biggest problem I have with use cases is that they are not structured. They are basically free text. For instance, if we have a use case Withdraw money from ATM, we may define that it has a precondition that Open account is performed, but we don't get any help from the method to see that. What happens if someone later changes the Open account use case or defines a Close account use case? How do we find which other uses cases that need to be modified? We can look through the old use case diagrams and find dependencies, but I can almost guarrantee that these dependencies have not been maintained after they were initially created. The solution to this is to connect the use cases to an object model. I don't mean a use-case realization with view and controller objects like ATM_Screen and ATM