General Grievous was rescued from a crash and turned into the cyborg that he is. While he was infused with midi chlorians as part of the process, he’s not Force sensitive, nor does he have Force-wielding capabilities.
During the Clone Wars, Grievous is time and time again given huge fleets to command, even though he promptly loses them most of the time. While he may not be technologically superior to the Republic, his army gets 100% accurate intel through Dooku, who gets it from Palpatine. So even though he always knows the location and capabilities of the Republic fleets, he constantly loses. He’s a terrible leader, constantly makes poor strategic choices, and often flees his flagships whenever he begins to lose battles.
Is there any explanation for why he’s kept as a general? Is it because there is no one better (because most of the Separatists, beyond the banking clan, seem to really just be droids)? Or is this just poor writing because the Clone Wars is targeted for younger audiences and Grievous needed to survive until Episode III?