Welcome to Android Central! Which LG phone do you have? Go to Settings>Wi-fi, tap Menu>Advanced, and make sure Wi-fi Scanning is turned off. If your phone is on Marshmallow, this setting is probably in Settings>Location, then tap Menu>Scanning.
I have an LG L41 with Android 4.4.2. Going to settings>wifi>menu>advanced wifi, there a choice that says "scanning always available" which is un-checked. It doesn't happen often, but once in a while, I find the wifi is on and searching for a signal.