Mine is the volume of their voice. If all that they can do is just talk too loudly with no reason for it and don’t control the volume of their voice. That to me is a sign that you’re a stupid fuck. Because people think the louder they are, the more righteous and attention seeking they are. Than it is to just listen, digest and respond accordingly to anyone talking around you.
Don’t ever go to Spain. They are loud as hell. They all yell at each other at full volume while having multiple TVs and phones blaring on speaker.