The angle held between the lead arm and the club shaft deep into the downswing, so the clubhead trails the hands and its stored energy is released at the ball instead of before it. Most players set roughly 90 degrees of wrist hinge by the top; keeping that angle while the lower body leads down creates a whip-like effect — clubhead speed arrives exactly where it pays, at impact, with the shaft leaning toward the target. Its opposite is casting, which spends the angle from the top. One caution the pros repeat: lag is the result of good sequencing, not something to yank on with the hands — forcing it usually breaks more than it fixes.