Great Pyrenees like to think for themselves, and don't much care what you want them to do.
I took my buddy Nemo to agility training. He can do all the tricks. He will not do any of them once he has had enough treats. Simple things like sit, down or stay all come instantly, when he wants the treats I'm holding. Any other time, unless I have real urgency in my voice, Nemo feels I'm presenting options. Sit generally results in lay down. Stay is often "wander off and lay down over there."
This Pyr has a blast just knocking the crap out of that obstacle course.