Is it an "Urban Myth" that some batteries willl only accept so many attempts to re-charge them before they roll over with their feet in the air ?
Apple staff told me that when I bought an iPad, so I let it go down to almost zero everytime before I start to re-charge it, and then put it on a timer so that it is no longer connected shortly after it reaches full charge, which takes about 4 hours.
It doesn't normally inconvenience me, but am I being unnecessarily paranoid.
( like everything else in Life - ask two people and get five answers.)