Doesn't that draw in electric type moves that are super effective.
Lightningrod gives Pokémon immunity to all Electric-type attacks and raises the Pokémon's Special Attack by one stage whenever they are hit by one. http://bulbapedia.bulbagarden.net/wiki/Lightning_Rod#Generation_V And that is very as it protects it from Electric-type Attacks leaving it with only one weakness
I like apple pie :-) I don't actually know!! it isn't particularly strong so its not to give it a bad point.
maybe its so it can be paired with something weak to electric in a double battle as a support pokemon
hope I helped!! :-)