Sometimes I wonder if there was a class somewhere. There's a surprising number of people in theater who do certain things. Certain annoying things. As if they all took a class together where these things were taught as if they were good and proper things to do.
Or perhaps this is a convergence of thought. The same logic that makes people independently hear one lyric in a Creedence Clearwater song as "There's a bathroom on the right." Perhaps entirely independently, the burden of acculturation, of ways other things are done and ways things are presented in movies and TV, has led to these same stupid things.
1) Leaving screws half-way in. Inevitably, a tech will loosen the screws to take down a flat, a panel, a jack, or even a scab, and will leave the screws in the holes. This can't just be laziness. You have to work at it to leave enough screw so it doesn't fall out, but remove enough so you can move the object that had been screwed down.
Okay, sure, I can see a possible theory going through their minds. They are thinking that each screw into a piece of wood leaves a hole, and enough holes, the piece will be destroyed. Except it doesn't work like that. The lifespan of a flat or flatjack is measured more by the wood itself, and the corner blocks. Those fail long before the number of screw holes get onerous. And re-using screw holes also destroys wood; each screw reams the hole out more.
And, yeah, it does work if you are just popping it off to get behind it and you will put it back in the same place a few minutes later. But the people who leave screws half-way out do this all the time. Every time. Including when the piece is going to be put in storage. Or stacked. Or thrown in the dumpster.
And what happens in the real world is the screws snag. Chunks of plywood don't stack properly. The screws get bent and twisted and snapped off in the holes, and gouge the wood much worse than a second hole would do. And the screws get caught on things. On fabric, causing expensive tears. On people, causing painful ones.
It's stupid. Don't do it.
2) Cutting the grounding pin off an extension cord. This one just has to be a case of a little knowledge being a dangerous thing. Presumably the pin gets cut or snapped off when someone finds they are trying to stick a grounded cord into an ungrounded outlet. And they are just educated enough to know it will still work fine that way. The electricity will still flow.
Through pipe clamps, through microphones, through the strings of electric guitars, through YOU.
Defeating ground is dangerous.
But, they might argue, they aren't going from a grounded circuit in the first place. Well, that's really the problem, innit? If you are plugging in a clip light for an orchestra stand, you don't need a fifty foot extension cord. The majority of the time that someone is trying to plug a nice grounded cord into something ungrounded, is when they are trying to run a power tool off an ungrounded, under-rated, fifteen amp household outlet. Or, worse yet, they started at one end with a nice grounded 20A outlet, but the first extension cord they reached for is one of those flimsy bits of 22 AWG zip cord suitable only for plugging in Christmas Tree lights.
Ninety percent of the time, the person who finds it necessary to cut the grounding pin off an extension cord is doing so because they are plugging the wrong thing into the wrong thing in the first place.
Oh, and as an aside. Plan your runs. Use a star or string topology for your pit wiring so power comes into the pit on heavy-duty extension cords, is broken out with surge-protected strips, and only THEN, after you have powered the amplifiers and other possibly noisy, power-hungry items, do you break into a fine capillary network of zip cord to finish up the orchestra stand lights. Of course the musicians will re-arrange themselves in the middle of the show and end up stuffing too many wall warts into one strip and running nasty bits of zip cord to things that should never be on zip cord...but you can at least start them out wired with economy, neatness, and safety.
Oh, yeah. When I find a nice grounded extension cord that has been sabotaged like this, I cut off the end. When it gets re-wired, it will be re-wired correctly. Ready Kilowatt to the contrary, electricity is NOT your puppy friend. It will cause noise, it will cause fires, it will cause pain, it can even cause death.
A lot of sound people think that defeating ground is the FIRST step in solving a ground loop problem. No. It is the LAST step. In fact; more often than not, the issue will be with floating grounds, and you'll get less noise by going around and making sure everything is properly grounded.
3) Staples. I know it is a pain, but remove the staples. Sure, in the press of events you may decide that a few tears in the duvetyne are worth it to get it off the platforms sooner. So you grab fistfuls of fabric and pull. But unless you are a cruel, cruel person, go back and pick out the staples later. I've put far too much blood on the duvy over the years.
4) When a cord is taped to the floor, remove the tape. THEN remove the cord. Sounds so simple! But nobody gets it. They grab one end of the cord and tear the whole mess up as one. The tape flips around and glues to itself and you will never get all of it off your cord ever again. (Especially if it is duck tape, which should never be permitted inside the door of a theater. When I see it, it joins the decapitated extension cords in the rubbish bin).
5) Fold it before you stow it. I don't care what it is, folding tables or work lifts with outriggers, the tech will inevitably fold the loose parts just enough so they can shove it into a closet. It will take ten times as long to get back OUT of that closet. Stow the legs and other floppy parts properly. Screw doors into flats. Fold and fasten down jacks. Remove loose shelves. Come ON, people!
6) Long thin things stored on edge. Don't do it. In the majority of cases, the space saved is an illusion; you had the footprint to store them flat without losing anything of importance. Especially, don't get cute and store them inside stacks of plywood or flats! They might look neat when you stack them, but sure as anything, the next time someone is shifting that stack to pull out a sheet, one of your little six-inch wide, eight foot tall pieces will come slicing out of nowhere like a guillotine.
I've lost work to those things (significant bruises meaning I had to take time off to heal). I've seen rental furniture destroyed by similar. I am only waiting for worse injuries to occur to someone.
If you have to stack on edge, then lash it. Anything else is unconsciable.
But then, this is really another case of what I call "Magic Magnetic Garbage." That is the theory that if you can somehow get it close enough to the garbage can, no matter how drippy it is, it magically becomes a solved problem (in reality, it becomes someone else's problem). I am convinced that the people who slip a fourteen-foot 4x4 on end behind a cyc are convinced in their animal mind that once they've successfully set it down without it falling over, and backed away, it magically never again will be a problem.
The sad reality is of course someone will need to go back there. Often as not, NOT the person who propped up a death trap. And the end result is torn drapes and expensive repairs and swearing and bruises and, sometimes, worse.