I recently replaced the battery in my 1970 Vette at 14 years 9 months. I never had it on trickle charge. Cranking was getting slower and slower with each long period of idle use. I really thought the battery was failing to give good charging under load with engine running. It didn't improve with the new battery. My alternator was replaced to solve that problem. Still, I didn't want to push this battery longer.

I'm on my 3rd Optima in about 6 years.  First 2 were replaced free, I think I had a bad trickle charger.  This one is doing fine.