LG G2 is not showing up in ADB even if I check USB debugging I can't find my device in ADB for my LG G2 phone running Android 4.2 ICS. I have enabled USB debugging.

What did I miss?
Make sure "USB Debugging" option checked and your driver has been installed properly.

You can try following step command:
1. adb kill-server
2. adb start-server
3. adb devices

Hope this help.