Primary reason, as discussed in
the 2016 Auditor General report (should link), appears to be for "identifying and analyzing fraud risks and trends, and checking the effectiveness of fraud controls and making adjustment."
The Auditor General report and IRCC response goes well beyond the scope of this, including other quality control elements such as enhancing IRCC and RCMP screening for criminality, but the structure of the PPQ-QAE is clearly oriented to identify indicators of
residence-fraud, and this is primary focus of the report as well.
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