Help with Battery Terminal corrosion and why

I have had excellent success with the felt washers and then spraying the whole terminal with Permatex High Tack gasket cement. The High Tack stays soft enough to 'heal' after connecting jumper cables or test leads.

I re-coat every year ... or two if I forget. I should add that I only do this on top post style systems. The truck in my sig line has side terminals and I do nothing to them.