What occasion turned out to be a disappointment when you went or found out later? List as many as you wish.
My answers are:
* The pictures I took in Rome all came out blank (film cameras were used then)
* The air show we were planning to see was so expensive to get in, we just turned back
* A trip to a coastal resort (Brighton) was ruined because it was never ending rain and high winds, plus the car parking system was ridiculous.
Now it's over to you....