Customers...
Guy begs me to move a big machine for him. Can't do it because of some prior obligations in the schedule. Get him in touch with a colleague who can do it right. Customer confirms. Colleague blocks off his schedule, makes travel plans including buying plane ticket. Customer then says he's going to have someone local do it, and that my colleague can come in after to 'get everything lined up.'
Yeeeaaaaah, no. Colleague says he's going to tell the customer he doesn't follow up other people's work, unless it's me or a couple other select guys. And I don't blame him. These things are big and complicated, and who knows what the amateurs will screw up along the way? That you have to find without anybody telling you what was done before you arrived.
Had one where I had to take the machine completely apart to its major components - like it ships - because they screwed up one detail that I specifically told them NOT to mess with. So it meant their cost of taking it apart wrong, then moving it, then setting it up, then me coming down there, then spending time checking it out, then figuring out they made a mistake that screws up alignment of 2/3 of the machine, then taking it all apart again, then re-aligning those 2 pieces, then putting it all back together again, and then - finally - getting to do the "lining up" that they figured was the only thing I needed to do.
Customers think they're saving money by having someone cheaper come do it. Almost never works out that way, and especially not on the big beast in question.