Haha! I saw this post on my feed earlier and had a good chuckle when I saw the discussions. It's always great to just have a laugh about it after everything is said and done. I do fall for these things from time to time as well, but I always make it a point to look at the big picture. In this case, it was a literal interpretation of it haha!

The blockage going to 3 was just so subtle, and the closed off passage from 2 to 6 could be easily missed because one would expect every hole is open. The leak in 7 would immediately make someone think that it's never going to get filled. If the image isn't enlarged, one could easily just miss 8.