What tool is most suitable for quick-service hairstyling?

A blow dryer is the most suitable tool for quick-service hairstyling because it allows for efficient drying and styling of hair in a short amount of time. This tool is especially valuable in a fast-paced salon environment where clients may be seeking a quick touch-up or style. The versatility of a blow dryer also enables hairdressers to achieve various looks, from adding volume to creating wave patterns, often in just a matter of minutes.

In comparison, while a flat iron and a hair straightener can provide polished looks and straight hairstyles, they require more time to section hair and apply the tool evenly. A round brush is typically used in conjunction with a blow dryer for styling, adding volume or curls, but it also relies on the blow dryer for effectiveness. Therefore, the blow dryer stands out as the primary tool for achieving quick and efficient results in hairstyling.