You gave advice to "...Run the phone down to automatic self shut off. Then charge it fully overnight. "
That is bad advice! That's hurts your battery!
Try to make sure you know WTF is going on before you write passive aggressive posts!
That is NOT bad advice. It does NOT "hurt" the battery.
These batteries and their charge controllers are designed for this environment. The engineers know damn well that phones will be run to exhaustion in the normal course of use.
Do you SERIOUSLY believe the engineers would allow you to drain a battery to a harmful or dangerous state?
The batteries have designed in protection circuits that cut off the battery WELL BEFORE any harm can come to them.
Power controllers (built into the phone) have no idea initially how low your battery can go before the battery internal protection kicks in. So it will tell you the battery is almost empty (maybe 5%) when in fact the battery on a new phone may well have 25% left. When you ignore the "Plug it In" warning, the power controller will obtain the actual charge state (measured by final voltage) to which the battery can be safely run.
Then it knows what the real limits of the battery is, and what previously was reported as 10% left will now be accurately reported as maybe 27% left.
Same for measuring the true full charge state. The power management controller has to see it to know it, otherwise its running from pre-programmed guesses.
Once you've done this once, normal usage will take care of if, and you may never have to do it again, because most people end up running their phones way down sometime in any two or three month period. But out of the box, your charge measuring circuit has only a guess about what your battery can do.
Please do some research before getting all high an mighty on the internet. This is common knowledge, and occasional full discharges are recommended for these batteries even by Apple and the battery manufacturers. They ALL have protection circuits that prevent battery damage. They are designed by professionals with engineering degrees, not kids playing with RC toys.