It used to be that Australia needed immigrants so that they would work and help to build and develop our country.
These immigrants were usually skilled at some trade or had other qualifications which would make them attractive to a small but growing young country.
These days immigrants (often in the form of refugees) are needed to swell the ranks of the unemployed, thus having the effect of placing a downward pressure on wages growth.
(It's "good for the Economy") 
I used to work in a profession which regularly advertised for people from other countries to come here to work. The industry said they couldn't find enough suitable Australians to do the job. So, instead of providing more affordable and suitable education for the Aussies here and offering them more attractive working conditions and salaries, workers from overseas are encouraged to come here instead. (this is still the case)
The net effect is that these new workers earn many times more than what they would have earned at home. That's the good news.
The bad news is that these new workers from overseas will work for less (or at least, will not agitate for more), leaving Aussie workers effectively competing with them for a job and struggling to gain even the meanest improvement to their wages and working conditions.
My point is that there is far more than just an humanitarian reason for our govt to encourage an increase in our immigration quotas.
