system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Why are the Separatists and their droid army so feared? It seems like they lose most, if not all, of the battles the Republic engages them in

Even their top general, General Grievous, seems to be extremely incompetent in military strategy, with him being beat back at almost every turn. Also, their droids are incredibly inaccurate for robots that have a built in aiming system.
gpt
Actually the sepratists won quite a few battles, especially in the beginning. It's just that most of them were "off screen". 

And while most of the droids (and to an extent higher ups) were pretty incompetent(all part of pappa palps plan) they still had staggering numbers on their side and a all around technological advantage(even if it wasn't fully utilised) 

Also dont forget palpatine, the leader of the republic was feeding them key intel so they always seemed one step ahead of the GAR (because they were)