A lot of how long a battery will last, is how you take care of the battery. I bought a new 2002 Honda ST1100 in Dec, 2001. I always kept a Battery Tender on it during long periods of not riding. It is easy to hook up, once you install the battery connections and have the plug hanging on the side of the bike. When we were in Las Vegas at the Cycle Expo in Oct, 2018, I talked to a Rep at the Yuasa Battery Booth. I asked him how long a Yuasa Battery will last that came in an ST1100 that I bought in Dec, 2001.
He looked at me like it was a trick question. I then told him that it was the original and he was amazed, being it was over 17 years old, and it still starts the bike with no problems.
He then suggested for me to take photos of the battery serial number as well as the bike VIN and a few other things and send to him.
Yuasa sent me a new battery and a Yuasa battery charger similar to the Battery Tender brand, but it also has hook ups for 2 batteries. I also had to sign some forms so that they could use my information for promotion purposes, showing that the Yuasa battery will last a long time if properly taken care of.
I have 6 Battery Tenders that I use on bikes, garden tractors and cars, when they sit for long periods. They are much better than your normal charger, as they do not continually put a high charge into the battery.
That is just one example that I gave about use of a Battery Tender to extend the life of a battery when in storage, or just sitting for a few weeks. Since I have been using Battery Tenders, my batteries last many years.