Most of us who bought our flat in before 1990s took up HDB loans. During the 1980's the loan interest rate was 6% and more. Now if we don't meet minimum sum, we have to 'refund' CPF not only the loan amount, but the CPF accrued interest which we would have ‘earned’ should we not used the CPF money for the flat. So our money goes from CPF to HDB. We pay HDB interest for the loan. Now we have to refund accrued interest to CPF. In summary, it is money into govt pocket all the time.
The idea of 'paying back ourselves' CPF interest rate accrued is so ridiculous! We don't have the right over our own CPF money. It is as if we are borrowing from both HDB and CPF for the flat loan.