Most amount of rods I will have on my boat is 10. Like I said I always go in with a game plan that suits what I'm comfortable fishing. So I don't change very much. Unless something has drastically changed since the time I prefished I wont change much. Prefishing is the best thing you can do. If I cannot prefish a lake chances are I will be power fishing and covering water with jigs, traps, and spinnerbaits, till I find an area or pattern. Then I will settle down and go from there.
Truthfully, I might change baits 2 or 3 times at the most if I change at all.