Scent, vibration, larger presentation, natural forage for a predatory fish. I will run straight minners on some poles and jigs and or road runners tipped with minners to see what the fish want that day. Crappie are visual feeders and some days they want color or flash mixed in with meat and other days they want just a gold Aberdeen and meat. Some days you can catch them with straight jigs or pony heads, certain times of the year you want catch me in a boat without minners though, no matter if they are needed or not.