Why is an alloy is often more useful than a pure metal

A pure metal has specific properties. Sometimes we need that metal but with modified properties. So for the modification of properties we make alloys.

Explanation; An alloy is a mixture of two elements, one of which is a metal. Alloys often have properties that are different to the metals they contain. This makes them more useful than the pure metals alone. For example, alloys are often harder than the metal they contain.