That's a good Q. For me it is not getting drunk. There is never any reason to get drunk. As soon as I feel I'm getting kinda buzzy I stop. Usually 4 beers and I'm a 240lb man.
Have never been even buzzy.
Get a typing software program--Mavis Beacon is good.
Take a typing test without any alcohol. Drink a can of beer.
Take same test again.
Drink another can of beer.
Take same test again.
Drink another can of beer.
Take same test again.
Consider if you'd like someone else driving with those changes in their thinking, fine motor coordination and physiology up and down a street your 6 year old only son was playing on . . . or driving on the streets you drive on . . .
So, to most people, starting to feel drunk is like the way I feel if I take an antihistimine that makes me feel drowsy. Kind of muffled, and fuzzy, and not quite myself. OTOH, when I feel that way from Alcohol, I'm just getting revved up.
Course there are plenty of people that like to get drunk and be somebody that don't turn out to be alcoholics.