Good morning Chris,
Thanks for your question.
My first thought is RSLogix/Studio 5000 is updating slowly, and not catching every count. Throughout the course you'll see it only updating about 1 a second.
But in listening to the motor (not shown) I think the Photo Eye may be out of alignment and catching the part twice per rev?
It would be good to know exactly which is happening, so in the 2021 update I'll make a note to make sure the physical hardware is in every video so we'll know for such next time 🙂
Please keep the great questions coming, and thanks again for this one!
Instructor at The Automation School