Spoiler alert for Avengers: Infinity War. Did Dr. Strange sacrifice the time stone to save Tony Stark from Thanos because out of the over fourteen million timelines he reviewed, Tony Stark was alive to fight Thanos in the one timeline they won? And in the other timelines, he was not?  There is a part two. And "winning" could mean that the lives Thanos turned to ash can be reversed if the heroes and their allies locate, confront, and force him to return all of those lives (similar to the story in the comics).