Bass fishing question

For anyone who fishes for largemouth bass. I have good results with soft fake worms but I'm noticing a drastic change. A couple styles would hit on a regular basis but now the bass completely ignore them. My lake is clear enough that I can see them approach the bait then just swim off. They used to attack the same bait a week ago. Is this a temperature issue, a time of day issue, or a seasonal issue?