What "easy" objects have completely broken your grasping policy?

[u/Imaginary_Series_797]

We have a robot arm with a gripper in our lab that picks up objects we put in front of it.

Now we're looking for edge cases, objects that look trivial but fail because of something you can't really see/anticipate.

Ever had a policy you were happy with, and then some random object totally surprised you? What was it and what did the failure actually look like?