While the quality of our batteries has always been excellent, the batteries we are producing today are the best we have ever made. Many of the "bad" batteries returned to us under warranty are just deeply-discharged and work fine, when properly-recharged. It's primarily a charger technology-related issue and not unique to Optima. In fact, some other AGM brands have dealt with it by simply voiding the warranty on their batteries, if they are found to be deeply-discharged. We didn't do that with our warranty, but we did create a YouTube video, which explains how to recover deeply-discharged batteries (I'm not allowed to post links).
We have enough of these "discharge-only" batteries, that we now sponsor the Chumpcar World Series and supply their teams with these batteries we now call adOptimas. We handed 100 of them just at Road America the other weekend.
Jim McIlvaine
eCare Manager, OPTIMA Batteries, Inc.