[Avodah] The Splendor of Clothes

[Prof. Levine via Avodah]

 From http://www.torahmusings.com/2015/07/the-splendor-of-clothes/

Rav Soloveitchik further added that wearing a Yarmulke, a Kippa, is 
more dignified than a baseball cap. He said, "If the President of the 
United States suddenly appeared and wanted to take a picture with me, 
would I wear a Russian hat, a baseball cap,- or a Kippa? That is the 
way we should stand Shemoneh Esrei when addressing the King of the 
Universe, HaKadosh Baruch-Hu.

See the above URL for more.  YL