The answer to this question lies in the events surrounding Voldemort's first attempt to kill baby Harry Potter. It was Severus Snape, a young and ambitious potions master, who, under the influence of the Dark Lord, played a crucial role in the attack.
While Voldemort himself inflicted the damage that left Harry with a lightning-shaped scar, it was Snape who cast the spell that disfigured Voldemort, leaving him with a flattened nose.
Snape, under the influence of Voldemort's Imperius Curse, was tasked with protecting the Dark Lord's secret location. He was unaware of the true nature of the attack and believed he was protecting the Dark Lord from being discovered.
However, Snape's actions in protecting Voldemort's location inadvertently led to the attack on the Potters. This betrayal of his own morals and the subsequent events of that night ultimately led Snape down a path of regret and remorse.
This act of unintended harm highlights the complex and tragic nature of Snape's character, a man torn between his love for Lily Potter and his allegiance to the Dark Lord.
