The shared responsibility model
After this short break, the team gathers again in the meeting room:

Charles: Let me give you an example to explain the shared responsibility model.

Alex: I am all ears.

Charles: You live in an apartment building, right? Can you tell me whether there are any security controls in your building?

Alex: Yes. We have cameras in the common areas, access cards to operate elevators, and videophones at the building entrance.

Charles: Great. And have you installed all these security controls?

Alex: Nope. They were already there. I guess when the building was constructed, the builder might have added all these things.

Charles: And you also have a lock and key for your apartment.

Alex: Definitely.

Charles: So, in this situation...