That if you're going to win people's sympathies, you can't be merely flawed, but a complete and total *******.
Seriously, I'm not kidding. Eamon makes the mistake of marrying the wrong woman, and is considered the unholy union of Rimmer Dall, Roose Bolton and Abaddon the Despoiler as a result, while Anora betrays the people who rescued her, leading them to be sent to a nightmarish dungeon to be tortured to death, and no one bats an eye.
Wynne dares to suggest you might wish to prioritize stopping an endless army of flesh-eating subterreanian monsters over your sex life, and is immediately condemned as a villain, yet Vivienne's self-proclaimed desire to restore a system of oppression that's led thousands of people to be tortured, raped, lobotomized and executed over the centuries (while having no intention of applying the same standards to herself, of course) is met with gushing about how sassy she is.
Merrill dabbles in blood magic in hopes of arresting her people's slide towards cultural extinction, all the while remaining one of the most compassionate and selfless people around, but is considered a moron because her mentor made the poor choice to let herself be possessed out of fear. Solas, meanwhile, deliberately and knowingly gives an ancient elven superweapon to one of the most evil entities in existence before viciously condemning everyone else for making choices he doesn't personally approve of, and yet is excused of all culpability.
Blackwall lies about his past while trying to become a better person, and up comes the cry about how he's a criminal rapist scumbag, yet Anders makes the person he loves into an unwitting accessory to an act of terrorism that kills numerous civiilians and kick-starts a world war, and out come the excuses about how a bunch of old nuns consituted an existential threat, or how it was gonna happen anyways.
The Grey Wardens have been saving the world for a thousand years, including cancelling the apocalypse on five seperate occasions, but are immediately vilified because a demon got into their heads and manipulated them, while the Orlesian nobility, who have been murdering each other over courtly favour and petty political squabbles since their inception (along with treating the lower classes like their personal playthings), yet everyone shrugs that off like it's nothing.
That's what this franchise and fandom have taught me; small mistakes, poor choices and differences of opinion are to be instantly and utterly condemned, while huge mistakes and genuine evil can easily be defended and forgiven.