Staple guns should be banned
Had a day's worth of fault finding with a TDR (an old CRT Tektronix one that weighed a tonne) because some dopey 'leccy had installed a new 10BASE-2 coax run using a staple gun in the Forestry Dept of the uni I went to.
The problem was that the numpty had missed quite a few times and put the staple through the coax. So he pulled the staple out and redid the job over the top. Problem was that withdrawing the staple dragged the shield through the centre conductor and shorted out the cable. TDR found each short, and since laying new cable wasn't an option it was a matter of cutting back just enough cable to fit two new BNC plugs and then join them with a barrel connector.
Had a weird one in the electronics lab too. This lab had 10BASE-2, but with the fancy floor connectors that allowed a cable to be plugged in that broke the circuit, diverted up to the PC, and then went back down again (totally superseded by 10BASE-10). The floor ports had little covers secured by a chain. Someone had used sink plug chain, the one with lots of little ball bearings. The balls would fall out, roll across the floor and down into a port, shorting out the special connector. Apparently took AGES to figure out the fault, but then all it needed was a strong vacuum cleaner to 'fix' it.
I don't miss 10BASE-2 in the slightest. The best part of going to 10BASE-10 was the part time work I had making patch leads for the computer centre (they were too cheap to buy them). I still have the wiring pattern burnt into my brain!