To stop Weapon X from creating more deadly soldiers, Wolverine sacrificed everything to stop them, resulting in the hero's death. In the Death of Wolverine storyline from Marvel Comics, Wolverine dies after shutting down the Weapon X program, resulting in the X-Men enforcer's entire body being coated in adamantium. The same metal inside his body ended up killing Wolverine, as he sacrificed himself in one of Marvel's most heartbreaking deaths.
Wolverine's mutant powers were famously enhanced in experiments by the Weapon X program, as the government research facility bonded adamantium to the claw-wielding X-Men. Unfortunately, Wolverine wasn't a willing participant in the program and ended up being physically and mentally damaged by the experiments, as they still haunt the hero to this day. Given all the pain and suffering Wolverine endured at the hands of the Weapon X program, he made sure to take them down given the chance, sacrificing himself in the 2014 comic Death of Wolverine to stop soldiers like himself from being created.
In original scientists from the Weapon X Program, Abraham Cornelius, attempted to recreate the experiment and sought out Wolverine to learn more about his healing factor - not knowing it was failing. A horrified Wolverine finds out Cornelius is trying to replicate the experiment that coated his bones with adamantium, and learns he has tested on hundreds of subjects. To stop the scientist from killing more innocent subjects, Wolverine smashes the container holding the adamantium and is coated in the hot molten metal. The metal hardens, resulting in the X-Men hero's death.
Ultimately, Wolverine's incredible sacrifice and death saves countless other subjects from being experimented on from Weapon X - and gets revenge, killing Cornelius in his adamantium form. Wolverine couldn't bear seeing more deaths in the adamantium experiments and shut down the project at the cost of his life. It's one of the hero's greatest and most tragic moments.
Remarkably, Wolverine's death lasted for years, as Marvel was pivoting away from the X-Men at the time as they didn't own the film rights to the characters. While Logan would eventually return and be freed from the adamantium, his death in the series remains one of his most iconic moments, as he sacrificed himself to ensure Weapon X didn't create more Wolverine-like weapons. It was a full-circle death and temporary ending for the X-Men hero.
