Why must refund or adjustment of CPF contributions paid in error be made immediately and no later than one year from the date of payment of the CPF contributions?

Any errors in CPF contributions should be rectified early while the documentary evidence is fresh. To encourage employers and employees to check their CPF contributions and come forward to rectify errors as soon as possible, any request for refund and adjustment of CPF contributions paid in error must be made immediately and no later than one year from the date of payment of the CPF contributions.