Cultural embarrassment
If you're visiting Sweden and you're trying to kiss someone on the cheek three times you will encounter difficulties and possibly even get harmed, at least if you bump into me. By and large, the Swedes doesn´t kiss when we greet each other, but if we ever happen to feel a little bit cultural we would stick to one kiss, that's it.
Try two and it would most likely generate some giggle, go in for the third kiss and it will definitely create trouble or awkwardness.
Personally, I have failed so many times by now that I would have been better off just apologizing beforehand and slowly back away from the situation.
I have headbutted people, mashed down my teeth into strangers foreheads, and yes, of course I've kissed people I never met before right on their lips.
This might be the only thing I don't miss about studying abroad and having to meet a lot of new people all the time because honestly, it is very difficult to make a good first impression when you just made a small gash in someone's chin...
Otherwise, there are other fun cultural differences that can create a lot of, let's say noteworthy, situations such as the fact that the Italians say "Chin-chin" instead of "Salute" sometimes.
So instead of saying "cheers", which we often did in restaurants and other alcohol related circumstances, we just shouted "Chin-Chin"!
What we didn't know, as our shocked Japanese friend had to explain to us, was that in Japan "chin-chin" simply means penis. So we are actually sitting in a fancy restaurant yelling "PENIS!" to each other.
Obviously, we continued shouting chin-chin after that.
Something else that I really didn't know is that in many countries it's very disagreeable to blow your nose in public. Imagine someone peeing on the floor, apparently that's about as bad as blowing one's nose outside the restroom. I guess to us in northern europe this is as normal as scratching your elbow if it itches, but to people from Turkey this is just straight up disgusting.
My poor friend Carla from Sicily learned this the hard way when she unwittingly was blowing her nose in a classroom filled with people from Turkey and got a bunch of disapproving and disgusted glances. Instantly her friend told her off and ordered her to go to the bathroom immediately and to stop being so filthy.
I'm so happy she did it first and saved me from the embarrassment, I mean I probably already headbutted most of them so it would almost be unfair if I also had to be the one who, unknowingly, kind of peed on the classroom floor...