It may be that when you speak (whatever the language) you speak it with a distinct accent. They may find it fascinatting when they hear their language spoken by someone with a different accent. Do you find this appealing? Author Kurt Vonnegut described his feelings: “All these varieties of speech are beautiful, just as the varieties of butterflies are beautiful.”
On the other hand, some people become irritated and wonder why the stranger cannot speak their language properly. Sometimes prejudice can play its part. Yet, with the constant increase of international travel, an open mind can be such an asset, since we can expect to encounter the situation more and more as time passes. However, by far the majority of people are intrigued and find it a refreshing change to hear their mother tongue spoken with a different accent.