I mostly fish inline spinners in late winter early spring, not because they won't catch year round, but because the grass and weeds make it too much of a chore, and there are better choices to fish around the green stuff then. Inlines have the "beginner" and "dink" moniker firmly stuck to them, and they are not untrue, but they are much more than that.
A spinner will not spin, or will be reluctant to do so for a few different reasons. First it could be the blade, either it's shape, size, or the balance it creates with the body, second it could be the clevis, wrong size, or burred or distorted, lastly it could be the bearing bead, some use plastic or hollow metal, which are more prone to create friction, and of course it goes without saying it could be the wire, or assembly of the spinner. I make my own, it's not hard, and I can make them do what I want.
A heavy double #3 with a bucktail behind it catches everything.