Yes, whenever the payment processor (Google/PayPal/etc.) does not immediately confirm back to our system that a payment was good and complete, then by default we do not offer any download link until that payment has completed.
Even for payment funding methods which should normally be instantaneous, PayPal often has lags in their system where their IPN (Instant Payment Notification) is delayed, so our system has no way of knowing those payments were complete until later. In those cases, we would not issue the download link until that IPN finally comes through.
If you wish to bypass this waiting for confirmation and just offer your download links immediately -- assuming all risk that a payment might not pan out after the download has already been fulfilled -- the setting is in your Seller Admin > Edit Account Preferences (this bypass setting works for PayPal payments only).