I would like to know why most organization in Qatar now requires a transferrable sponsorship ( transfferable visa ) from applicant before giving them job.

They do not want to take the responsibility of sponsoring an applicant ( foreign worker ) from his or her country to work in Qatar. They prefer to look for residents with valid papers in Qatar to give their jobs to leaving out foreign based applicants.

The Qatar labour law requires that the applicant pay for the travelling cost of the worker from his or her country to Qatar and from Qatar at the end of the contract.

naijaspeak: I would like to know why most organization in Qatar now requires a transferrable sponsorship ( transfferable visa ) from applicant before giving them job.

Because Africans and Nigerians have a very bad reputation for getting into a country and then going illegal.
They end up un-employed and begging or commiting crime on the streets.
This is why the crack down on young people getting visa.