Although I utilize vests for style, I realized that sometimes a vest is better to wear than a jacket or sweater for functionality. Because a vest covers the center part of your body, it keeps an important part of your body warm. Someone who is doing outdoor activities should wear a vest for layering purposes that allows his or her arms to move freely. Sometimes when you wear a heavy jacket or sweater, it gets difficult to move around. Also, in the summer time on a chilly night, a vest may be all you need because a jacket could be to heavy.
FASHION TIP: Some vests are great for style while others are best for warmth. When you find one that does both, I advise you to invest in it.