Kevin Feige reveals that Thanos' home planet of Titan is now abandoned after he was stopped from doing what was necessary to save it. We've also learned that Avengers: Infinity War will feature flashbacks to the Mad Titan's youth, expanding his backstory and shedding some light on why he's spent his life hunting down the Infinity Stones and becoming the Marvel Universe's greatest villain.
In Avengers: Infinity War, Thanos is convinced that the universe is dying and needs his help, hence why he enacts a master plan to save it...by using the Infinity Gauntlet to wipe out half of all known life. The Mad Titan doesn't want the universe to suffer the same fate as Titan, hence why he feels that killing billions is what's best for the universe. The only thing standing in his way is the combined might of The Avengers, the Guardians of the Galaxy, and Wakanda's army.
