Winter coming, need advice for this newbie...

Care to explain why when I would leave the bike battery in the cold over the winter it was only good for one season yet when I stored it inside I would get several out of them?

Ooh! Ooh! I can! Batteries slowly lose their charge. A fully charged battery will not freeze, but a low or undercharged battery will. As the battery slowly loses it's charge it becomes vulnerable and will freeze. That can destroy batteries, or at the very least shorten their life. And small motorcycle batteries are especially vulnerable because they don't have a large charge to start with. Keep them warm and they last a lot longer than leaving in the cold.