If you watch this video you can see how the deck pitches up and down on the barge/landing pad.
https://www.youtube.com/watch?v=0qnmvvueSl4
Musk tweeted the speed at landing was good. One of the legs didn’t lock.
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However, that was not what prevented it being good. Touchdown speed was ok, but a leg lockout didn’t latch, so it tipped over after landing.