I didn’t know loft was intentional. The word made me think of accidentally releasing the ball two feet off the ground and it slams down and meanders to the gutter.
It means to release the ball in such a way that the ball doesn’t make contact with the lane at the moment of release, but may strike down some distance from release. I’ve seem some bowlers who loft the ball so bad that it contacts the lane ½ the way to the pins. Not too good for the lane surface!!