Spent 11 hours on a laptop that just needed the BIOS clock reset

A customer dropped off a Dell Latitude last Monday saying it would not connect to anything on their home wifi, and I figured it was a driver mess or a bad card. I reinstalled the wireless drivers twice, swapped in a known good card from my bench stock, and even ran a full network stack reset from the command line. Around hour nine I pulled the battery out just to check the coin cell, and sure enough it was sitting at 2.1 volts instead of 3. A five dollar CR2032 and a quick clock set later, the thing grabbed the network on the first try. All that time wasted on software when the hardware was telling me the answer the whole time. Does anyone else have a habit of checking the easy stuff LAST, or is that just me?