My first name is "Jean-Baptiste". "Baptiste" is not a second or middle name, however I noticed that it's not unusual for native English speakers to address me just as "Jean".
I don't mind it at all, I'm not offended and find it actually charming, but it would be quite unusual for a speaker of my native language (France's French) to call me like that (either native speakers address me with my full first name, or they use various nicknames - and the nickname is never "Jean").
So I'm curious as to why many native English speakers seem to spontaneously call me "Jean".
The two hypotheses I have is that either my full first name might be a bit difficult to pronounce (so just saying "Jean" is easier), or because they mistakenly think that "Baptiste" is my middle name - as compound first names are unusual in English (correct me if I'm wrong).
I'd tend to think it's the second option, as I noticed that it also happens in writing, but I'd be interested in having the insight of people who know English language and English-speaking cultures better than I do. Maybe I'm completely on the wrong track!
When it happens, I usually don't have the opportunity to ask people why they are calling me like that (e.g. in a professional context we usually don't have the time for that, plus in this kind of situation I don't want to make people feel like they offended me), that's why I ask this question here.