I've got two.
Many years ago, by then-boyfriend and I planned an 8-week backpacking trip around Europe. It quickly became apparent that he was a dreadful travel companion and much more of a controlling arse than I had previously realised. I remember many nights lying awake wondering whether I could leave and somehow continue the trip without him. I didn't, but we didn't last long after we got home. So it wasn't the location or accommodation, just the dreadful choice of company.
Second was my most recent overseas trip to Bali. I've been many times and had a perfectly lovely time. This was a much-anticipated trip and the first proper holiday since covid. I'd had a shocking year and just needed a relaxing holiday. I was taking DS on my own to meet up with friends.
My friend (whose judgement I trust implicitly) had booked somewhere she'd stayed before. DS and I arrived the day before them and were utterly disappointed with the place, it was shabby and run down. It obviously hadn't fared well during the pandemic lockdowns. That night, DS woke up in the middle of the night and vomited all over the place.
The area where we stayed had become something of a Russian influencer enclave. A lot of young Russians have escaped conscription and set themselves up in Bali. Some businesses run by Russians seem to be fronts for drug dealing. Every second shop seemed to be for cosmetic treatments including lip/cheek fillers. And the traffic is so bad, it was pretty much impossible to go anywhere else.
Although nothing dreadful happened, the whole thing was just distinctly disappointing, and I had paid a fortune for it!
@coxesorangepippin Japan is nothing like that now. It's easy to pay with cards and there are ATMs in convenience stores all over the place. All the subway signs have English translations, and the Google Translate app is very helpful. Foreign smartphones work and you can also get a local SIM or rent a portable wifi device. It's actually really easy for non-Japanese speakers to get around.