1. For Years After Infinity Gauntlet, Thanos Was A Changed Person
Thanos is commonly thought of as Marvel's deadliest villain, and that reputation stems from the Infinity Gauntlet arc, written by Thanos' creator Jim Starlin and artists George Pérez and Ron Lim.
What most people forget is how Thanos was contented after the conflict. For years to come, he was basically written as a much more heroic character than ever before,
working to save the universe with old enemies like Adam Warlock and the Silver Surfer.
2. Loki's Face Turn Coincided With His Greater MCU Popularity
Loki is one of the most important villains in Marvel history and is responsible for the formation of the Avengers. For years, he'd battle his brother Thor, the Avengers, and other heroes
of the Marvel Universe, always causing mischief and trying to make himself more powerful. However, an interesting thing started happening after he
made his first appearances in the MCU and Tom Hiddleston's portrayal of the character made him a fan favorite.
Loki was given spots on teams like the Young Avengers as Kid Loki and his own solo series, where he played a more heroic role than ever before.
Comic companies have often given villains face turns to grant them more exposure, and there were years in the mid-2010s that Loki was basically a hero for the first time.
It was a way to get MCU fans to buy some comics, which is usually a futile gesture.