It satisfies an exhibitionism interest and also excites the voyeur. To those with those tendencies it creates a lot of anticipation
My wife and I live in a very hot and humid climate. We never wear underwear. We strip our clothes off often during the day and take cool outdoor showers. Underwear is pointless here. We also are boating people, so no underwear is allowed.
My ex used to go pantiless @ work. I worked there also, one day she was on a second- level catwalk that you could see through while walking underneath, I looked up and saw her entire lower package! Quite a sexy sight, but I can only imagine the women, and men on her crew saw this too. She got mad when I catcalled her lmao... I Said well what do you expect? She wore panties after that.
Whenever I go to a movie I wear a dress and no panties!! Once my boyfriend fingered me and I came all over the seat!!
After a few drinks, her panties would come off, wear short skirt or dress, She loved showing smooth look, in early 70's, when shaving was rare. She liked to shock, both men and women.