Wha reason did the national labor relations act give for allowing labor unions to form?

The reason behind allowing Labor Unions to form was that collective bargaining guaranteed equality and preserved the continuity of the business, as it secured commerce from "injury, impairment or interruption" and rehabilitates the relation between employer and employee.

Collective bargaining ensures equality and protects the flow of business.

The above is the reason which the National Labor Unions give for allowing Labour Unions to form.