I've been around motorcycles and motorcycle batteries for almost 50yrs now. Back in the old days with water filled batteries they must be charged all winter or removed and brought indoors, otherwise the water would freeze and leak acid all over. Thankfully those POS are long gone. With a modern battery, my own experience to keep them working is do nothing unless the motorcycle sits for a month or more, then charge with a battery tender before starting. In my opinion and experience, keeping on a maintainer, charger whatever too much ruins more batteries than what benefit they serve.
I read guys all the time complain they only got 2yrs out of a battery and it was always sitting on a charger. Well Hello, that is why it went to crap! I'm coming up on 9yrs old on a GL1800 Honda battery that still works good as new as I haven't ruined it by overcharging when not using.