Why has the government sought to privatise Australian visa services?

This information has been extracted from the REPS NOTICE PAPER: Questions In Writing - 016 Ms Sharkie: Minister for Immigration, Citizenship, Migrant Services & Multicultural Affairs about "Why has Govt sought to privatise visa services?":
MS SHARKIE: To ask the Minister for Immigration, Citizenship, Migrant Services and Multicultural Affairs—
(1) Why has the Government sought to privatise visa services.
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