One is decoration;

Second, if you don't think the sour taste in the drink is enough, you can squeeze the lemon yourself.

In addition, lemon has a strong antioxidant function, and some drinks, especially fruit juice, are easily oxidized by direct contact with air, so putting lemon slices on the cup mouth can keep the color and taste of the drinks.

Lemons are very commonly used in cocktails. It can bring a delicious sour taste and a fragrant smell of fruit. Moreover, it is rich in vitamins and has strong antioxidant effect, so it is a beauty artifact. You westerners have a soft spot for this.

Later, I gradually ignored the original role, just for modeling and beauty.