There is nothing that says "android phone" or "android adb interface" and I see no yellow interrogation points. Every time I either connect my phone, reboot my phone while connected, or change to usb debugging when my phone is connected, windows update always starts downloading drivers. Before windows update does anything, the lg mobile update tool recognizes the phone without any problem. It managed to stay that way, but then when I switched to usb debugging on my phone, windows update started up again and downloaded drivers that would cause me to go through to whole process again, restarting my phone and re-installing the lg usb drivers.
It seems as if I'm getting some kind of driver conflict, but that's the best explanation I can come up with.
EDIT:
After some more mucking around, I found out the following: While restarting the phone after enabling usb debugging (while connected to the computer), in the device manager there is an "android sooner single adb interface" (or something along the lines of that) listed. The lg mobile update tool is also able to communicate with the phone without any issue.
After the phone is completely restarted, anything labeled with "adb" or anything along the lines of that disappears, and the lg tool can no longer properly communicate with the phone.
Now what happens when I restart the phone without usb debugging enabled:
While restarting, the lg tool communicates with the phone with no issue. Nothing to do with adb shows up in the device manager. Lg tool no longer can communicate with the phone when it is completely started up.
I should also note that windows update is longer downloading any drivers.
I'm thinking something is misconfigured inside the phone, which causes it to not detect as an android ADB device after boot. When the android logo is on, your ADB interface is activated and when the launcher appears, all parameters set in settings fire up. Did you check in settings/storage? There's an option there I think that forces the phone to detect as a mass storage device, that usually deactivates the ADB interface on boot...
If that still doesn't work, factory reset maybe?