Trademark look[1][2] or signature look[3] is the characteristic clothes or other distinguishing signs used by a certain character or performer, making the person more recognizable by the audience.
Politicians may also have trademark signs, such as the suit of American President Barack Obama[4] or the Merkel-Raute hand gesture of German Chancellor Angela Merkel.
[7] Some trademark signatures may have started as in-jokes, but have then come to have been recognized by a wider audience.
Popular personalities like Steve Jobs and Mark Zuckerberg are known for their signature look.
The reason shared is to save the sheer amount of time spent on deciding what to wear daily.