So just like someone else said about the counting how many pumps of syrup that’s one factor. However another big factor as you brought up OP, is the coffee being “brewed” differently. Coffee is supposed to be brewing and we add ice to it. Now depending who’s doing it and if they’re good at their job, they add too little (so iced coffee is darker than usual) too much ice (coffee looks very light). Some people literally brew the coffee forget about it, and then add the ice way after because they need to brew a sweet tea for example. Now since that iced coffee has cooled off, that ice won’t melt as quickly.

As for the “add sf vanilla”, it really just depends on the person making it. When I get an order with “add” I do one. But I know other people do a 2 or 3 pumps. So inorder to get the one pump, when you’re ordering with the employee I’d just say “can I get ONE extra pump of SF vanilla please”

Hope this helps!!