Maps. The very limited availability of the Retina iMac when released which put a hole in that years Q1 earnings. The very public John Browett debacle and the mishandling of Bob Mansfield's "retirement," then "unretirement." And finally, yes, the watch. A stumble is a stumble not a face plant fall. It means something didn't go as smooth as it should have. Do you honestly believe the AW launch was smooth with the awkward way customers had to preview it? Couldn't buy it in the store for months. Couldn't be delivered to online customers who bought 2 minutes after the online store opened for weeks after launch. Look at the front page regarding AW sales and tell me that isn't what you honestly think is a stumble.
On the whole Cook hasn't had any clear major victories. That is my point. If he has please let me know. Happy to be corrected.