Instead, victory was achieved because the enemies of Thanos (read: just about everybody) were successful in taking advantage of his lack of experience with an overabundance of power.
He forgets that his true power ultimately exists with the use of the Infinity Stones, and when he leaves his body he opens the opportunity for the Gauntlet to be taken right off his hand.
Following an epic battle, Thanos manages to become the literal center of reality, leaving his “flesh” form behind — and while he believes that this move sheds him of all vulnerabilities, the exact opposite is actually true.
The original Infinity Gauntlet series progressed to see Thanos go head-to-head with some of the most powerful cosmic beings in the universe, organized by Silver Surfer and Adam Warlock among others, but by the end of the conflict it wasn’t about strength — partially because the Mad Titan proved to be stronger than any and all other god-like entities.