Vertical Sensitivity

I’m curious on what people do and think of the difference between vertical and horizontal sensitivity.

I was playing with horizontal being twice as high to what vertical was the opposite of the default settings. The reason was so my aim would be level but recently I found randomly my aim would dip down or up for no reason. I checked my sticks in the test app and every thing seems fine. The thing that makes no sense is the dip down/up is quicker than when I’m moving horizontal.

Cause of aiming being erratic and not feeling consistent I’ve been changing my sensitivity a lot to keep up and it was working for a long time for me but cause it’s being way more irritatic than normal I’ve decided to give default a try and I’m wondering what is the reason for the default setting.

My 2nd (2nd cause it was on default ages ago) impression of the default setting is on 10 sensitivity I find vertical too fast but I’m comfortable on horizontal being between 4-8 and vertical no more than 8.

Would there be any other kind of ratios that people use and what is the reasoning?