Electronic TRANSACTION delay by the bank

When paying a beneficiary online the payment leaves your bank account but does not reflect in the other bank account. However if you are prepared to pay this can happen immediately. There appears to be no reason for the delay other than a payment. In other word this boils down to a monetary issue. The bank cannot give a reason for the delay except to blame the other bank, however if you pay there is no delay so blame must fall at the bank receiving the payment. We are in a digital age and there is no reason to delay a payment except for the bank to benefit or gain from the delay.