Str0udy

It all varies from experience to personal preference. I've been on PC for roughly 7 years, 2 of them years I had my DPI at 1200 and sometimes 1600 - With this DPI I was so inaccurate (I had low sens too), the mouse was catching my jittery hand because of it and overall it just affected my aiming - When I went to a lower DPI and higher sens... the DPI filtered out my hand jitters (Same as @Quackerjack) - this then helped improve my aim and performance due to the crosshair being more consitent in where I'm telling it to aim and over the years I slowly built my aim down (From a csgo standpoint) to 400 DPI and 0.8 sens (Used to be 1200 DPI with 1.8 sens) TL;DR - It's all down to the user themselves, if you want to lower your DPI then do it in increments of 100 and every time you lower it via 100 - play some type of aim trainer (Like the one mouse-sensitivity link) and keep adjusting it until you're comfortable.