For me it's the water temp. Right now where I'm fishing the water is in the 30's so bait is the ticket for bites. Once the fish start spawning movements than it will be jigs no bait. If the fish are chasing the jigs than no minnows but when they get tight lipped I'll use minnows. I prefer just a minnow and hook no jig. Sometimes the jig will spook the fish. Nothing like a minnow allowed to swim free to insight a bite from a nutral fish.