Why is registration of an immovable property so important?

The purpose of registering transfer of immovable property is to record the signing of the document. The ownership and transfer become legal only after registration, i.e. the ownership of the property is rightfully transferred only upon registration before the sub-registrar. Another significant benefit of paying registration fees and stamp duty is that the same are eligible for tax exemption under Section 80C of the Income Tax Act, 1961.