Dramatic re-enactment of an actual discussion I had today...

"Can you make these changes for me?"
"Sure, no problem."
"Great, thanks. So, what's the timeline on getting that done?
"Well, when do you need them by?"
"Well... I kinda need them now, if not yesterday?"
"I see. Well, strictly speaking, 'now' wouldn't be a timeline at all, would it? Graphically represented, the duration between 'now' and 'also now' is more of a dot than a line. Shall we call that a 'timedot' from here on out?"
"I don't think I follow you..."
"OK, let's start with 'I need that yesterday', that might be simpler. If we can grasp 'yesterday' then maybe we can come back (actually, that would be 'come forwards') to timedot in a minute."
"So... you're saying you don't know when it'll be done?"
"Not at all, I'm just saying that the timeline for 'can i have that yesterday' is very different to the timeline for 'can i have that now'. It starts at now and goes backwards to the point in yesterday you'd like to have this. You understand that, right?"
"Uhh... I guess so..."
"So, do I already have it done?"
"Huh? you're asking me if you already have it done?"
"Sure! Because if you need it yesterday, and that's something I can do for you, then I've already done it, and you've already got it. In fact, you've been sitting on it now for a few hours at least. What's the damn hurry if you're not going to do anything with it now I've given it to you? Really, you people amaze me sometimes."
"So, hey, I'm sorry, I must have forgotten about it. Maybe it's in my Inbox - I'll go look for it, and let you know if I need anything else."
"OK, great, thanks for stopping by."