As someone who writes software for a living, I'm always thinking about testing. Not that I like testing, but testing is the only way to validate your work. Even the most confident programmer checks the basic operation of his work.. right?
Well, it seems that the same rules don't apply when installing a new car stereo. At least, not on a Saturday morning. I just spent over $300 on an MP3 car stereo, and was shocked to find when I drove off that there was a shreiking sound coming from the speakers which exactly matched the motor's speed. Having spent my youth installing car stereos, I immediately knew the problem - The earth wire had not been secured. It's fine when the stereo runs alone, but not when the motor is on. Great.. I'll just turn the motor off at the lights, shall I?
A simple test would have been to run the stereo, at the same time as the motor. Not too tough, right? It goes to show that a little time spent making sure the job is done right will save time in the future. Not only my time, but the next poor sap who will be handed this job in his lunch break.. I can only hope its the *same* guy who stuffed it in the first place.
Of course, such a lesson is timely reminder to all programmers. NEVER assume that just because you got it right every other time, that you don't need to test this time.. Of course you do!