10 Worst Things Captain Marvel Has Ever Done
6. Letting The Puppet Master Kill Himself - Ms. Marvel (Vol. 2) #18
The thing with fighting supervillains is that you get a first-hand look at all the worst stuff they've ever done. Often, this is stuff so bad that you just can't forgive it - which is exactly the case when Danvers comes into contact with the Puppet Master for yet another time, only to discover that the villain had enslaved an entire harem of women with his mind control powers, and was selling them to the highest bidder, or otherwise using them for manual labour until he could find someone messed up enough to buy an actual human person.
While this alone would be enough to infuriate anyone, the Puppet Master also makes the interesting decision of kidnapping and controlling Araña, a superhero who Carol regarded as both her protege and a sort of adopted daughter. As such, she's unimaginably furious with the villain for all his misdeeds, and so when he tries to blow himself up, she let's him, actively addressing the fact that she could have stopped him killing himself, but simply chose not to.
To make matters even more sinister, Danvers lies to the rest of her team by telling them there was literally no way she could have saved him, meaning she also told a bold-faced lie to pretty much everyone who put their lives in her hands.