You know that's a good question, but honestly I don't think they've had a single AAA bomb this generation. They've had a few underperform at launch (Syndicate and Watch Dogs 2) but they've also noted that those games had strong legs and ended up successful.
I don't think they've had a single big budget AAA game this gen we could classify as a "bomb"
The worst performer was probably The Crew, at least relative to investment (6 year development cycle), though they had pretty low expectations out of that one by the time it launched.