Frequently, Doctor Doom is portrayed as an individual with complete faith in himself and in his importance to the world. He considers himself above the deities that populate the universe, and has worked to take over the planet and rule it with an iron fist. Ultimately, Doom really believes the planet will come to love his leadership and grand vision. He's arguably Marvel's most flexible and enduring villain, capable of endangering the entire universe or a single hero depending on the story.
But while this means that Doom is likely always going to be a villain -- and that any attempts to redeem Victor Von Doom will be short-lived -- it's also been used as a means of exploring his genuine desires. Across the history of the Marvel Universe and with the help of alternate univeres, Doctor Doom's true desire has been revealed to be a beloved hero, like many of his enemies. But even in alternate timelines where he does become a better person, Doom's own inner demons always end up preventing a brighter future.
Doctor Doom Always Loses - Even When He Wins
Due to the nature of the Marvel Universe, it's rare for Doctor Doom to ever achieve any lasting victory -- with even his successful strategies in storylines like Emperor Doom ultimately coming apart under the strain of his own failings and the actions of rival heroes. In other realities, though, Doom was more successful -- and yet, still found wanting. In What If...?: Secret Wars #1 (by Karl Bollers, Jorge Molina, and Jeff Powell), Doom kept the Beyonder's power and was able to defeat the rest of the heroes and even destroyed the Celestials -- but at the cost of the Earth itself, which was almost wiped out in the conflict. What If...? #22 (by Don Glut, Fred Kida, Gaff, Dave Simons, and Tom Orzenchowski) introduced a timeline where Doom heeded Reed Richards' warnings during his college experiments . This, in turn, set off a chain of events that turned Doom into a globally beloved hero. But his pride kept him from sacrificing himself to Mephisto to save his people and his wife Valeria. This resulted in his bride becoming a prisoner of Mephisto's dark realm.
In both of those realities, Doom's actions were perceived as heroic, at least in his own mind. He was elevating humanity beyond cosmic scales, or fighting villains across the globe. But in both worlds, Doom was left haunted by his choices, and even gave up his godlike powers in What If...? Secret Wars to partly restore the planet and a form of humanity that he could rejoin. The core-Marvel Universe Doctor Doom of Earth-616 has also been shown wanting similar futures, including in a false reality created for him by the Marquis of Death in Fantastic Four #567 (by Mark Millar, Bryan Hitch, Paul Mounts, Cam Smith, Andrew Currie, Victor Olazaba, Mark Pennington, and Rus Wooton). In this imaginary timeline, Doom joining the heroes against the Marquis solidified his redemption -- leading him to take up a deceased Mister Fantastic's place within the Fantastic Four. This was a moment of true peace for Doom, one created solely to torture him with its false nature.
Doctor Doom is His Own Worst Enemy - Literally
Doom's dream of becoming a heroic version of Reed was the happiest moment of his life -- and the Marquis' plan and further efforts to break Doom only inspired him to become more hardened and ruthless. Even glimpsing timelines where Doom could actually overcome his ego to become an actual hero aren't safe from the angry machinations of the Earth-616 Doom, who demands the world's respect but always finds a way to ruin it for himself. After encountering a variant of himself who'd become a globally beloved hero (on top of a loving husband and father), Doctor Doom learns that to become a hero, he must let go of his anger and embrace his greatest rival as a friend. This is so offensive to Doom that he uses the Ultimate Nullifier to wipe out that entire reality, erasing the proof that he could genuinely become a better person -- a truly great one -- if he could just get over his darker impulses.
Doctor Doom could easily be one of Marvel's great heroes. But even when he gains victory over all creation, even when he becomes the beloved icon to the entire world, there's something about the villain that keeps him from finding redemption. His secret desire to be a hero and to be as such can't compete with his often destructive darker side. His ego, and his refusal to buckle under any form of pressure, even when it would save the soul of his beloved or force him to confront his mistake, is what drives one of Marvel's most brilliant men to become its most dangerous monster.