Finish with both arms straight
Great players have both arms straight and the trail side moving through the shot as they swing through impact. This movement controls the swing circle. If you are struggling with distance, direction, and contact, some form of breakdown is usually happening through impact: the wrists may get active, the elbows may bend, or the body may stop moving.
Channel: Danny Maude
Watch official source at 1:14Why this context matters
This is the impact destination he trains with the putter-grip device.