I pulled a very standard Dave move not too long ago. Actually, it's so standard, that I feel like I should patent it or something. It'll be my own personal business process, one that I can charge for every time I see a company going down this route. I had some shelving to install from Ikea (generally cheap, but quite functional store). I thought I had taken care of all the measurements and gotten everything right, but when I got down there, it turns out I had forgotten to measure the depth. Normally, this would not have been too big a problem, but I had not yet taken out my existing shelves, and there were two potential options to buy. Whenever there are two potential options I naturally always choose the wrong one and then am forced to return it.
In some ways, I act very much like a branching algorithm on a chip. Rather than drive all the way home, to figure out what the correct measurements were and then drive back, I always buy the good with my best guess, and then take it home. Of course I got it wrong and had to return it, but if I guessed right, which I had a 50/50 chance of doing, no returns. It seems I fail at guessing though much worse than 50/50. I think I need to improve my guessing.