Recovery is included on a separate partition from the main Android OS on all Android devices.
You can boot directly into recovery mode and use it to factory reset the device, delete the cache partition, or apply software updates.
It can help you fix your device.
1. To start you will need your phone switched OFF, so please do that, and hold down power button.
2. Now press combination of Volume down button with power button together.
3. Now just wait for a LG logo and let go of the buttons.
4. And this is it! after few seconds your phone will end up in recovery mode.
5. To navigate here you have to use your volume buttons and to select use power button.
What does it for? In the past, a phone is more of a device used to make calls or text. However, it's much more than that.
Most Android devices are now defaulted with a fairly simple Recovery mode with features like Reboot System Now, Apply Update from ADB, Apply Update from External Storage, Wipe Data/Factory Reset, Wipe Cache Partition, Apply Update from Cache.
Just like a lot of other things with Android, even the Recovery Mode can be customized to do more things.