Boundary/manual question

Hi there! Love your work!
So I have a question, I know that in the past I think I’ve heard you say an example of you meeting up with a friend for dinner (or something) and them being late. That you said something along the lines of if they are late you would tell them, if you aren’t here by X time I’m leaving, and then you’d leave.
(I might have the exact specifics wrong but that’s the gist of it).

So isn’t this having a manual for a person expecting them to show up on time?

I am getting confused on what certain expectations (having a manual) are ok in order to honor ourselves?
If we accept everyones behavior under the premise of it being something from a manual we have for them, aren’t we then accepting poor behavior or not being true to what we feel we need or deserve for ourselves in relation to how others treat us in how we relate to one another?

What about having certain standards for ourselves?