My wife and I recently bought iPhones for both of us, and my mother in law was staying with us and she had a new iPhone as well. So imagine three iPhones sitting on the kitchen counter, all with Strum as the ringtone, and lots of calls coming into each phone all day long since we just had a baby every family and friend is calling. Total confusion.
Then we started changing our ringtones to fix the situation, but we were forgetting which phone had which tone.
Mother in law is gone now, and I started making custom tones, so the situation has improved. Thank god.