Question

why electroplating required

Answer 1

Electroplating changes the chemical, physical, and mechanical properties of the workpiece.it improves corrosion resistance .  An example of a chemical change is when nickel plating improves corrosion resistance. 

Answer 2

A major benefit of this approach over electroplating is that the power sources andplating baths are not needed, reducing the cost of production. The technique can also plate diverse shapes and types of surface. The downside is that the platingprocess is usually slower and cannot create thick plates of metal.