[dekhn]

How does that help debugging why your device didn't come up on the network? There are a number of reasons the device won't come up; often those are not easily deduced from a log file but can be easily debugged with a serial connection. Also that doesn't require you to mount the SD or reinstall the image.

[davidmaitland]

A serial adapter is great if you have one. But for the average person who may have picked up their first Pi free with a magazine is highly unlikely to have one. For most people changing two files is a pretty quick, safe and easy way to get wireless networking going with minimal extra hardware. Although you could easily remount the SD card and view the log files if you needed.