Something people don't seem to understand about damage dealt

I hear so many people thinking they're godly for the damage dealt and others aren't contributing based off it and completely ignoring kda.

I feel I need to clarify for this for people so let me give this scenario (im just going to be using random numbers to prove a point probably wont seem too logical)

A fully built has 4000 hp and is being AA'd by a 0 item and once mundo reaches around 100hp he uses his ult and regains full hp back making jinx start over in which case by time he's at 100 hp again his ult is back up and it restarts from there(lets say 3 times)

As oppose to a fully built AAing who manages to kill him faster than he can regain meaning you killed him before he reached full hp (lets say he got up to 1200 hp max)

Through logic this means the 0 item jinx did more damage over time because mundo constantly regained his hp back. Meaning the 0 item jinx constantly took mundo from 4000 hp to 100hp 3 times. 11700 damage has been dealt to mundo

Now when you look at the fully built jinx who takes him down BEFORE he regains the hp back. 4000hp to 100 up to 1200 down to 0 meaning she dealt a total of 5100 damage to him.

I'm really sick of people flaming in the champ select lobby crying about "I did more damage to them to you" to argue who did the most. Something as small as this can keep you from realizing your mistakes and prevent you from being a better player.

Nobody wants a Vayne thinking she can build rabadons and figure it's op because she did more damage than a twitch. (No this didn't really happen just saying it as an example)