How do you know it takes three seconds for the other party to continue the conversation they started?

It can just as well go like this:

- Bob writes "Hi" and I get a notification

- I enter the chat and wait for Bob

- 30 seconds later the indicator shows he's typing something

- 30 seconds later, still nothing

- 30 seconds later the typing indicator goes away

- I go away. Eventually Bob follows up with the actual content.

That was frustrating for me, not because of some issues I need to work with, but because Bob kept me on hold while he's trying to figure out what to say.