Great post. Just to add onto what has been stated.

Risk ranking and filtering is also particularly helpful in situations in which the portfolio of risks and the underlying consequences to be managed are diverse and difficult to compare using a single tool. Risk ranking can also be useful for management to evaluate both quantitatively-assessed and qualitatively-assessed risks within the same organizational framework.

http://www.fda.gov/downloads/Drugs/…/Guidances/ucm073511.pdf