oooh a fun one! I love The Print Handbook, and own a few of the editions. Bought a bunch for my mates back in uni and use it regularly for checking things. Unfortunately it couldn't help with my mistake.

I dont know the exact print run somewhere in the 10-20k, but a CD album of a very famous musician was printed and shipped with half the track listing on the back cut off by some artwork. It was fixed for future reprints, but out there in the world are thousands of albums where you can't read the track listing...

Spelling error on the inside front page of a client brochure that had a print run of 120,000… heat reduced by the fact that 3 people at our end and 2 people at their end had supposedly reviewed it, so not entirely my fault.

Its not my mistake as fortunately I've been lucky enough to not make any real big ones that weren't caught before press, but a now defunct studio I know of once had a contract for one of the grand slam tennis tournaments.

It wasn't a contract to work on any of the larger, main media campaigns they were running as this was just a small 3 or 4 person studio. So most of the work was designing extra collateral and signage as required when the need would popup in the lead up to the tournament. Obviously for a small studio, it was a super high profile client.

One of the jobs was to design pull up banners to line the players tunnel as they walked out to the court. There was one for every player in the tournament, and all of them were on display for every match, and they were just arranged in a random order.

In the first match, the two players started to walk out towards the court, and were to stop and wait at the end for the umpire before walking out. One of the players —who was one of the better players in the tournament and at the time a very well know name— was standing by his banner whilst standing at the front waiting. It was, just by chance, the second or third from the front. When he glanced at his banner, he and everyone nearby instantly picked up that his name was spelled wrong.

No more banners after that. If they were ordered differently it's likely no one would have noticed.

I misspelled the german word "einfach" as "eifnach" in 1m high letters, printed over an exhibition stand.

The company I worked for then never had more visitors at an exhibition.

11,000 copies of wedding invites sent to printer without doing color separation. Blue turned brown and the clients frowned :<

I once worked on a catalog for upscale office chairs. The book had around 170 pages printed on legal sized sheets and finished with a complex double glued binding.

Turns out all the SKUs for custom parts (which accounted for a large majority of their revenue from high end clients) were one digit off for half the pages. Yikes.

Luckily it was caught before the massive run had begun but a lot of the Initial print setup and test runs had to be thrown away.

TL;DR: Put the wrong URL on a bunch of prints, fixed it with a rush order of stickers.

Similar to the first mistake OP mentioned, mine is along the lines of a typo. The company I worked for was launching an online community for their customers. We were throwing a big launch celebration event to get customers registered on the site. Many of the print pieces included the url which was a subdomain of our primary website. Instead of putting "community.ourdomain.com", I put "ourdomain.community.com"... which ofcourse makes a big difference.

We had already spent so much on printing the typo (brochures, coasters, posters, etc), and it was the morning of the event.. so we ended up rush ordering a bunch of stickers with the correct URL that were perfectly sized to cover each URL.

I stayed late covering all of the hundreds (thousands?) of wrongly printed URLs.

Edit: Fortunately, none of the larger prints had the incorrect URL