if you've ever messed up a dimension or a hole position on something you're building, don't be too hard on yourself.

at least you're not the Cisco design engineer who caused an entire product line recall by placing the mode button (which resets the switch if held) directly above an RJ45 port.

it's pretty impressive to fail so hard that you become a worldwide internal meme at a company the size of Cisco. back when I worked there, I saw this image used in slide decks and on posters in several different offices.
(I should've really said "Cisco design engineering team" rather than just one engineer; this is very much a combination of process & oversight failures)
@gsuberland I was going to say just that: that this is not an individual contributors fault, is the whole process that failed. #BlamelessCulture works better for avoiding these kind of things.