Having a mobile phone is great when you need to talk on the go, but if you have a faulty battery, then you have to carry charger along with you throughout the day.
Many things can go wrong with a phone's battery, from the so-called "memory effect" to plain-old worn out batteries. Some problem can be corrected, but unfortunately, most of the batteries need to be replaced.
Did you know that even if you do not use your phone, it still uses battery life? This phenomenon is known as self-discharge.
If your mobile phone is switched off all the time, the battery life is still being used. If you do not turn it on every few weeks and charge it, the battery will die permanently.
If you have a cell phone that you only use in emergencies or are keeping "just in case," it is a good idea to turn it on and charge it at least once a month to keep it from self-discharging the battery.