Marvel Comics has had plenty of questionable moments over the years, but arguably the most controversial is when Hank Pym hit his wife Janet Van Dyne in an issue of The Avengers. Pym's legacy has forever been tied to the shocking moment - however, the panel was originally supposed to be drawn much differently and would have changed how readers viewed Pym.
In The Avengers #213, Hank Pym, then operating under the alias of Yellowjacket, was reprimanded by the Avengers for reckless behavior during battles, as he used his "sting" at full-force against a villain. After determining he crossed a line, the Avengers court-martial Pym, suspend him from the team, and ask him to turn his Avengers I.D. Pym immediately turns to the lab in hopes of building a robot that will show he's worthy to the Avengers. Janet, AKA the Wasp, investigates after Hank doesn't go to bed when he's supposed to, and finds her husband to be quite upset. After trying to stop him, Pym slaps her in the face and tells her to "shut up."
It's shocking to see an Avenger commit domestic abuse, and understandably, the moment has always been associated with Pym's character, even decades later. But, Marvel's editor-in-chief at the time, Jim Shooter, would later reveal that the slap was supposed to be an accident. Back in 2011, Shooter wrote that Pym wasn't supposed to intentionally hit Janet, but instead was supposed to accidentally strike her. According to Shooter, Bob Hall drew the infamous panel as Pym hitting Van Dyne and they ran out of time to fix it.
In that story (issue 213, I think), there is a scene in which Hank is supposed to have accidentally struck Jan while throwing his hands up in despair and frustration—making a sort of “get away from me” gesture while not looking at her. Bob Hall, who had been taught by John Buscema to always go for the most extreme action, turned that into a right cross! There was no time to have it redrawn, which, to this day has caused the tragic story of Hank Pym to be known as the “wife-beater” story.
When that issue came out, Bill Sienkiewicz came to me upset that I hadn’t asked him to draw it! He saw the intent right through Hall’s mistake, and was moved enough by the story to wish he’d had the chance to do it properly.
While Shooter might have intended for the story to feature Pym accidentally hitting his wife instead of intentionally doing so, Yellowjacket's actions in the comics don't really back up that idea. When he's on trial in front of the Avengers and Janet reveals her bruised eye, Pym tells her to "shut up woman!" before unleashing his new robot creation on the superteam. The comic still comes across as sexist regardless of how the moment was supposed to happen versus how it happened on the page.
Marvel never intended on Pym being a wife-beater, however, but thanks to some tight deadlines, it's perhaps the one thing most fans remember about the character. It ruined Pym's image so much that he's largely been used as a supporting character in the comics ever since after being one of the core Avengers. Thankfully, the Marvel Cinematic Universe's portrayal of the character has repaired Hank Pym's image somewhat - but still, thanks to the comic, it's forever fractured.