Dry-aged beef has a stronger smell than beef that's not been dry-aged.
It's caused by the natural enzymatic and bacterial changes that occur during the aging process. These changes give the meat a deeper and more complex flavor. It's a flavor that many people find more appealing.
During the aging process, the moisture in the meat evaporates, which concentrates the flavors and makes the meat more tender. This also causes the surface of the meat to become darker and form a hard crust, which can be trimmed off before cooking.
The aroma of dry-aged beef is often described as nutty, earthy, or similar to blue cheese. This is because the bacteria that grow on the meat during aging produce compounds such as lactic acid, which contribute not just to the meat's flavor but also the aroma.