If you dislike Lucius Malfoy you'll be pleased to hear this.
Lucius Malfoy was hardly ever loved in the Wizarding World of Harry Potter. In fact he was widely hated by wizards and muggles alike. But do you ever wonder what became of him, after we last see him after the Battle of Hogwarts? Malfoy's actor Jason Isaacs wonders as well, and has come up with an interesting theory. If you've ever disliked Lucius Malfoy you'll be pleased to hear this.
Isaacs, who couldn't be more different from Malfoy in real life, has no sympathy for his character, by the sound of it. The Malfoys, last we saw them, were retreating from the Battle of Hogwarts like cowards, not surprisingly due to the fact that through the entire series they have been. The entire villain exterior the family worked to put up was completely washed away when they left Voldemort to fight by themselves.
Behind that exterior, Malfoy Sr. is just a scared man, wanting to be validated, wanting to be a right-hand man, and to prove he is powerful. Isaacs agrees. Isaacs talked to Syfy Wire during an interview about the actors part in Audible's new The Tales of Beedle the Bard, and explained what he thought happened to his character after the battle.
"I was pretty sure of what had happened to him. I don’t know if anybody else needs to agree because that’s the fun of it, isn’t it? I think he was broken in Azkaban completely, and he was broken even by having to go there because the dream that he had held out for a long time of being Voldemort’s right-hand man and being celebrated as having kept the flame alive. [That notion] was shattered pretty quickly when Voldemort came back."
Malfoy's whole world was turned upside down after Voldemort's defeat. He was one of the Death Eaters that had claimed he'd been under the Imperius Curse the entire time, and made to do Voldemort's bidding. This was of course false, and Malfoy then spent years basking in the wake of Voldemort's downfall, thinking he was the most powerful person besides the Minster of Magic himself.
Even though he does try to wreak havoc with the Chamber of Secrets, his loyalty to Voldemort only went as far as how much power Malfoy could gain from it. When Voldemort did return, Malfoy tried to assure him he'd been loyal but it was lies. And when he fails to retrieve the prophecy, Malfoy gets caught and sent to Azkban. From then on Malfoy loses himself and his reputation, and when he gets out, a shattered shell of a man.
"Onscreen, you can see he’s always slightly stubbly and red-eyed and drinking whenever he can," Isaacs said describing how Malfoy looked when he got out of Azkban and returned in Deathly Hallows Part 1. "I always thought he drank too much. And then, in the final battle at Hogwarts, it became clear to him, particularly when Narcissa and Draco ran off, that there was no place for him in either future. Voldemort was not gonna have him by his side. He’d already [taken] my wand at the table in Malfoy Manor, which is public humiliation, almost castration."
When the battle finishes there's nothing left for Malfoy, now completely stripped of the life he'd been living before Voldemort's return. But how could he run with away with his family? The power almost outweighed his family all these years. But in the end there's nowhere to go but with his family. There can be disputes on where or not he loved them though.
"Were the Death Eaters to triumph, there’s nothing good waiting for him. And, of course, if the Death Eaters lose, there’s nothing good waiting for him," Isaacs continued. "That’s why that last shot of him is him just stuck in the doorway there with his wife and son disappearing in the distance and Voldemort disappearing into Hogwarts. [Lucius is] thinking, ‘What the hell do I do?’"
So when it's all done and Malfoy goes into exile, Isaacs thinks he became a complete hopeless case. While Draco eventually has a family and does redeem himself, even earning a nod from Harry at the school drop off, Isaacs believes Malfoy is home, rotting away.
"I think what would’ve happened afterwards, is that he would become a shell of himself. His money would protect him because money always protects people, and I think he would’ve lost — if he ever had any — the respect of his wife and his son. Society would shun him, and he would cower inside his mansion and drink himself into an early grave. And frankly, deserve it."
Hard words of truth from Isaacs, but in a sense they are probably true. In fact, you could say Malfoy caused more harm, at least from behind the scenes, than Voldemort ever did. He spawned Draco didn't he?