Why we need it is a question for the sponsorer of the visa I.e the employer who in average has to shell out $15k to lawyers and government agencies to hire some

Why we need it is a question for the sponsorer of the visa I.e the employer who in average has to shell out $15k to lawyers and government agencies to hire someone in h1b visa. It is NOT decided by your or my political or social preference , it is determined by market forces and the need of employers.