Quote Quoting Wryan (view post)
My interpretation is that he put his faith in Tony to be the right person for the right moment, that he banked on Tony to do what he foresaw was necessary in an ocean of almost impossible odds. He probably still didn't like him, but he did believe in him. Perhaps he had a backup plan in case things did not go right, but the battle was a little too chaotic to depend on that. He just had to be there to help nudge Tony into seeing the choice.
What? No. This one is easy. In the 14 million different scenarios Strange saw with only one scenario where they came out winning. That one event needed Tony alive. Thanos was going to kill Tony in IW and Strange also knew the only way he could keep Tony alive, would be to give up the soul stone. Tony would never have perfected the time machine or made the Iron Man Gauntlet, which means the events in Endgame would never have occurred.

They bring it up twice in Endgame to remind people why that decision was made in IW. It definitely relied on things falling into place, but Strange saw and knew what needed to happen. The Ancient One also knew this.