Slightly offtopic: I live in a city in Brazil whose heritage is basically german so I know a lot of people trying to learn german here. A particular friend of mine used to work for an IT german company and went to Germany a couple of times and he said every time he tried to speak their language they'd frown at him or feel like "conversation's not flowing" and switch to english. Other friends living in Germany (Stuttgart, Munich, Berlin) and also in Switzerland (Zurich) said the same happens to them with some frequency. I never heard about it happening with other languages or in other countries, so why is that? Any germans out there care to comment on this?
Edit: just to make it clear, this is purely out of linguistic curiosity
Depends on who you are, and how good they know you. Germany is a country that historically had a lot of low skilled poorly educated immigrants working in professions that require almost no skills. Those people never really integrated (not always their fault).
When unknown person approach a German with broken/half-broken/non-perfect German skills, that German has immidiate prejudice about your social status and education level. If your friend is from Brasil, I guess skin colour also plays a role here. Happened to me numerous times. You will get much better treatment speaking English, since that level the playing fields and then they consider you as an equal. Also happened to me numerous times.
So yes, the only way to actually speak German in Germany and not be intimidated is to speak it with people that you already knows and you can consider friends.
Australian here, but I can confirm that the times I went to Germany and tried to speak German, almost everyone pleaded with me to switch to English. I don't think my German advanced much as result. I was even briefly mocked by hotel staff (who were otherwise great): "Ahh yes, you are the one person in this hotel who only speaks English."
Taxi drivers were an exception, they did not seem to have strong English skills. As a result, the most enjoyable German conversation I ever had was with an elderly taxi driver as we stumbled through our knowledge of each other's language.
There are also other possibilities why they preferred English (Swiss here, so take it with a grain of salt when I refer to Germans).
To show off their English skills. Although this can even happen when their English is worse than your German. Especially Germans are really proud to be "international" even though it's not always justified.
Or they don't want you to stagger about in a language you don't know very well. So some want to be polite and spare you the trouble to speak it. Of course that doesn't help you but you should then insist and say something about "learning this beautiful language" and then usually they can't deny you this.
In IT it's quite custom that anybody speaks English when somebody is around that doesn't speak German as you are expected to know the language well enough. After all in IT, you need English every day. For Zurich, which has a great number of foreigners, this applies as well.
For Switzerland in general, remember that the Swiss dialect is quite different from Standard German and there are many Swiss who are not that comfortable speaking Standard German so switching to English is an option when they actually don't want you to notice how bad their German is.
I think this was his personal experience, or maybe his german level is too basic to be useful. I’m a brazilian living in Germany and people here are very open and forgiving about your german even if you are still learning and make a lot of mistakes, they really like their language and prefer it over english if it’s possible, at least that’s my experience.
The same thing happened to me in China when I tried to speak Mandarin. Fortunately, however, there were many people who couldn't switch to English because they didn't speak it.
> I never heard about it happening with other languages or in other countries
Same thing happened to me all the time in Japan (to be fair, my Japanese is essentially non-existent except for a handful of phrases) and France (significantly more proficient, but still not a proficient speaker). The Japanese in particular seemed put off by butchering their language.
Edit: just to make it clear, this is purely out of linguistic curiosity