Imperial Stormtroopers seemingly have improved aim in The Mandalorian season 2, episode 4, "Chapter 12: The Siege", but why is that? In the Star Wars franchise, Stormtroopers’ inability to shoot accurately has been a subject of confusion and mockery among fans and characters in-universe. The Mandalorian and Star Wars Rebels are particularly merciless in referencing Stormtroopers’ ineffective aiming skills. Despite this, "The Siege" featured a surprising level of competence from Imperial Stormtroopers. The Stormtroopers stationed at Moff Gideon’s Nevarro base managed to score direct hits on Din Djarin twice during his infiltration of the base, though he obviously survived, due to his blaster-proof beskar armor.
Throughout the original trilogy and non-movie material from both canon and the original Expanded Universe (aka Legends), Stormtroopers are bafflingly incompetent marksmen, with clear shots at characters, sometimes at fairly close range, missing their targets. Stories in both continuities have implied various reasons why they’re such poor shots. Some, like Jedi Outcast and Star Wars Rebels, imply that their helmets obscure their vision. Jedi Outcast and its sequel Jedi Academy also imply that the E-11, the blaster primarily used by Stormtroopers, is a generally inaccurate weapon. There are several problems with both of these explanations. Why do Imperial Navy Troopers and other military personnel who don’t wear helmets fire with the same level of inaccuracy? Why do Rebel heroes, armed with E-11’s, fire with pinpoint accuracy? Why would the Empire knowingly equip its troops with ineffective gear in the first place? The real answer has nothing to do with Stormtroopers’ gear or training because their marksmanship isn’t poor, it’s inconsistent, and there are in-universe and real-world reasons why.
There are numerous examples of Stormtroopers being accurate shots in Star Wars movies. The first time Stormtroopers appear onscreen, they easily defeat the Rebel Troopers stationed aboard Leia’s vessel, the Tantive IV. In The Empire Strikes Back and Return of the Jedi, Stormtroopers easily blast C-3PO and R2-D2. There are many more examples of Stormtroopers shooting with impeccable marksmanship throughout non-movie material in both continuities as well. In Star Wars, Leia implies that the Stormtroopers aboard the Death Star wanted her and her allies to escape to lead them to the Rebel Base. This is plausible, but the most likely explanation for Stormtroopers’ inconsistent marksmanship is simply that they shoot exactly as accurately (or inaccurately) as the story needs them to be. Imperial Stormtroopers are well-trained, well-equipped, and deadly soldiers, but they’re hampered by the all-powerful force known as plot armor.
In Star Wars, a Stormtrooper had no problem hitting Leia with a stun bolt, but aboard the Death Star, the heroes needed to win their firefights, so the Stormtroopers were spectacularly inaccurate. When the heroes of Star Wars Rebels are armed with blasters, the Stormtroopers are similarly poor shots, but when Kanan or Ezra use their lightsabers, the Stormtroopers easily score direct hits that the two deflect with their blades. In Jedi Outcast and Jedi Academy, Stormtroopers who are Jedi Mind Tricked into helping the player are noticeably better shots than they are normally. At the end of The Mandalorian season 1, two Scout Troopers riding speeder bikes shoot down Kuiil on a fast-moving blurrg because the plot needed Kuiil to die. Moments later, the two Biker Scouts, while standing still, can’t hit a transmitter lying on the ground for the sake of a gag.
With all of this in mind, it’s no surprise why the Stormtroopers in The Mandalorian season 2, episode 4 were able to hit Din Djarin twice. The plot needed him to survive, and thanks to his armor, taking direct hits from the troopers wouldn’t kill him. This means the troopers can hit him as many times as they like, while they're noticably less accurate against Greef Karga, Cara Dune, and the Mythrol in the same episode. Without plot armor getting in the way, Imperial Stormtroopers are, as Obi-Wan Kenobi once said, “precise.”