Goku is primarily renowned for eliminating Dragon Ball villains before they pose a significant threat to the Earth or even the cosmos, but the Saiyan warrior came dangerously close to inventing one of his own—one who might have turned out to be the worst in the entire franchise.`
Goku first appeared in the opening chapter of Dragon Ball, and it became clear straight away that he was an uncorruptible hero who would never hesitate to battle evil. In a few of his initial journeys
Goku single-handedly destroys a global fascist organisation, stops a neighbourhood gang from terrorising a hamlet, and kills a villain who genuinely believed he was the king of demons and had the power to match.
In essence, Goku is the best there is. How then did he nearly produce the most lethal antagonist in Dragon Ball history? The same quality that made Goku such an incredible hero in the first place—his propensity for mercy—also provides the answer to that query.
Akira Toriyama's Dragon Ball chapter 257 depicts Vegeta, who travelled to Planet Namek to acquire the Dragon Balls and use their wish-granting abilities to become immortal, meticulously slaughtering Frieza's greatest soldiers.
Vegeta encounters several enemies who laugh in his face at the idea of a lone Saiyan being powerful enough to defeat them, but Vegeta proves them all wrong and gets closer and closer to his ultimate goal.
Vegeta has been working with Lord Beerus to develop Ultra Ego, the divine energy that a Destroyer uses. Vegeta might still train his body hard enough throughout his eternal life to figuratively become a Destroyer God himself, however his Saiyan strength would be limited because he couldn't approach close to death to gain power-ups.
It would be very terrible if Ultra Ego Vegeta became immortal and never overcame his nasty nature. This would have happened entirely as a result of Goku's decision to be merciful in Vegeta's early Dragon Ball career.