Every wet cell battery needs to have the
electrolyte level checked regularly.

If you didn't check the level between June and October and it is now down to
the lead plates, that could be considered lack of maintenance.

If you have a cheapie charger that you keep connected most of the time (rather
than a "smart" charger), you could be boiling away your electrolyte by over
charging.

If the battery is three years old, it may be approaching the end of the trail
in any event. If so, recycle it, get the best battery
you can afford, and take special care of it.