system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] What's up with stun?

Six major documentaries and a stun weapon is only used once (on Leia). Why does a culture historically dominated by Jedi Knights place such a low value on less-than-lethal weapons?
gpt
There are a few problems with stun weaponry that make it very uncommonly used, especially by the people featured in the documentaries.

1. Stun technology is not identical to blaster technology.  Setting a weapon for stun is not as simple as adjusting the power of the beam.  A blaster bolt will always detonate on impact, with the power level only determining the energy release and concussive force of the shot.  A stun shot is a completely different energy emission, and requires its own circuitry and focusing coils to fire.

2. Stun shots are not focused.  Due to the different mechanics of a stun shot, the energy discharge does not remain small and focused like a bolt.  They expand as they leave the barrel, meaning that they dissipate over range, and they are not precise.  The effective range of the stun setting on an Imperial-issue Blastech E-11 is approximately 20 meters.  Anyone further away will feel a slight (or possibly painful) tingle, but anyone struck by the ring before that point will be stunned.  Thus, it is not possible to precisely stun one person in a crowd.  You'll need stun batons for that.

3. The stun effect does not last long.   Depending on the model, it could be as short as 60 seconds or as long as five minutes.  In either event, it does not take a combatant out of the fight for long.  In order to completely disarm an enemy combatant with stun weaponry, the soldiers would have to stop their advance and stuncuff everyone, leaving them vulnerable to attack, and bogging them down with a massive load of stuncuffs.

4. Stun circuitry is either large or expensive.  The most cost-effective stun option on the market is the CS-33 Firespray, which is a rifle in its own right, and completely incapable of lethal fire.  If you want to make a more compact weapon, it gets more expensive very quickly.  In fact, the single most expensive component in an E-11 rifle is the annular stun focusing coil.  Due to the cost, it's not always practical to add a stun setting, especially if it will be rarely used.  The Naboo Royal Guard and the Imperial Stormtroopers are both regularly used as a police force, and thus have a need for capturing people alive.  The Grand Army of the Republic and the Trade Federation Droid Army do not perform police duties, so the cost of adding a stun setting to their weaponry was deemed unnecessary.

To be honest, it's points 2 and 3 that are the most critical.  It is simply not time effective to stun and then stuncuff soldiers in a battle.  That's why droids and clones were so popular in the last days of the Grand Republic; nobody felt bad when a clone or a droid died in a fight.