Mahi Mahi, (Dorado, Dolphin fish - whatever you want to call it), Wahoo, etc. are too smart to go after a lure if it is moving slow enough for them to get a good look. These fish strike at lures going 7 - 8 knots.

I also have had poorer luck in recent years. Anecdotal evidence that the seas are getting fished out. Ten years ago it was like shooting fish in a barrel.