Dead battery behaviour?

The battery on my 990 has been showing signs of being on the way out for a little while now.
I have just come back from 3 months in Saudi and found that the battery cannot crank the bike despite having been on the C-Tec and showing all green lights.
I had the battery tested and both the state of health and voltage gave back readings of 100% (12.63v and 212SAE).
The battery guy insisted that the battery was not at fault, but I decided to buy a new one none the less.
Upon fitting the new battery it swung the motor to life at the 1st push of the button.
Now, I noticed that the battery I removed was 12S when it should have been a 14S which surely in my mind isn't much of a difference (yet clearly it must be).

Anyway, all is well that ends well.
Thanks to Chris and team at Flying Brick for recommending Deltec - I never would have thought of looking there for a bike battery. The other guys I phoned around to did not have stock and I want to ride!

BTW - R649 for the correct 14S Deltec battery, which I thought wasn't too bad.