10/11 month old male started to spin. never on marks only on Back. He didn't do it on the back pile only did it after I had him doing overs then sending to back pile he would spin. I fixed it or so I thought. I would No here! and indirect pressure on sit and send. After a couple times of that he never did it again. Fast forward to today. I sold him and his new owner messaged me that he did a little back pile with him today and he spun everytime. So why do yall think dogs spin?