What are Risks of rejecting Australia PR visa

Many people may have this question in their mind before applying Australia PR to know what are the risk of rejecting visa.
In my experience, I have observed following reason that may reject Visa:

1. Incomplete document not sent even after they remind with in time frame.
2. Fake document like qualification or Experience because some they call and verify.
3. Medical report not good
4. Police record not good

Apart from above, I don't see any major reason to reject visa.

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