system
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human
[Star Wars] why are battle droids so dumb?

Like their robots everything they do is programmed in. Why even give them self awareness if they’re also gonna be idiots? Why not just make them mindless kill it’s?
gpt
B1 battle droids (the skinny "roger roger" types) were not meant to be soldiers. They were designed to be security droids in extremely low-risk environments, like VIP rooms and expensive theaters that catered to the upper class. They were mostly just mobile blaster platforms that made a small area appear safe, even if the droids weren't seriously meant to shoot at anything. 

On top of that, they were built as cheaply as possible. Their programming is bottom of the barrel to go along with their clunky joints and relatively limited movement. They used to be so cheap that all of their processing was done from a control ship, rather than inside the droids themselves, because it was a massive cost saving measure. This combination of bad programming and intentionally weak combat ability is why they gained their infamously stupid reputation. 

But they could be built in the millions in a very short amount of time, so their incompetence could be overshadowed by sheer numbers. Even if half of the forces deployed in a battle are destroyed, there are still overwhelming numbers of survivors who could tear down what little was left of the Republic resistance. 


We've seen droids like magnaguards and even dark troopers with much more expensive programming and physical bodies, so it's entirely possible to make a very threatening combat droid army that can dominate in battle. But no one is willing to bankrupt themselves to purchase an army of several million units. (which is coincidentally exactly what the Republic did when purchasing another wave of clone troopers near the war's end)

And one final note, Darth Sidious may have forced the separatists to keep using faulty and cheap droids for the entire conflict as part of his grand pantomime. The separatist army looked huge and scary at the war's beginning, which scared a lot of people into giving him the power he craved. But when his narrative needed to shift toward a Republic victory, suddenly all of the holonet news channels were flooded with footage of battle droids being blown apart in spectacular fashion. That might not have been so easy to orchestrate if the separatists used a more competent fighting force.