It is usually a pre-qualification & risk-based pricing factor related to the issuance of mortgage loans by a financial institution.
[1] When obtaining a mortgage, the funding lender relies on the standardized valuation methods of an appraiser to assess a monetary value for the specific piece of real property on which a loan will be secured (e.g. a residence).
The lender will then justify the loan amount (and other risk-based pricing) factors as a percentage of the appraised value of the property.
For example, home owners wishing to gain access to their increased equity in their home may obtain a mortgage valuation to prove its value has risen and thus justify increasing the amount of their mortgage.
Also, the various states of Australia each have a Valuer-General's Department, which regularly assess land values in all municipalities and shires for the purpose of issuing property tax notices.