I was just thinking about all the stupid crap I saw and had to fix back when I was an installer. Some classics would have to be:

-Lamp cord as speaker wire

-4ga power wire with an 8ga ground

-And lets not forget Old Faithful; the power wire through the door jam

I know there are a ton I am forgetting. What are some of the worst things you have seen?

 

I found that pic on this webpage devoted to bad installs and equipment...
http://www.ghettoinstalls.com/

 

ive seen tinfoil twisted together with the power wire to connect it to the amp. Ground the same way.

 

I have ran a 8ga power with a 4ga ground because I was too poor to buy the power cable in 4ga. Also my buddy grounded his amp to a crowbar. And I have left the hazard light switch dangling when I tore my dash apart since it is needed for the turn signals to work. That is all I got in my head for now.

 

A long while back when I borrowed my friend's amp, I didn't want to drill any holes for ground. The next best thing was pinching the end of the ground wire on the bolt that holds down the spare tire!

 

my moron friend uses screws as temporary fuses when his blow.........all these reasons we listed are why there are professionals that do this.....

 

Here's one I just remembered:

A guy came in one day wanting to know what he was doing wrong. I took a look and was shocked. Apparently he didn't understand how an amp produces power, because he was using 18ga wire as his power wire and had it hooked up to the constant power lead behind his deck. He couldn't figure out why he kept blowing fuses.