People who use addons are so apparent...

[Yeol]

I think I understand what OP is referring to.

There are some mechanics in the game where you cannot tell the safe spot right away. You need to wait for 3s~5s into the cast bar or boss/arena animation to figure out the safe spot. Yet there are people who will immediately move to the safe spot before anything is clear.

I didn't raid in a while, but one example of this was E4S. People with addons knew where titan is going to punch (front or back) even before his punch animation shows it. So people can dodge and pre-position earlier.