Why does an approved deal registration still show the option to submit it for approval?

If the user has either the Sales Administrator or Channel Operations Manager job role, then they will still see the Submit for Approval action even on approved deal registrations.

This is because sales administrators and channel operations managers can resubmit approved (or rejected) deal registrations to allow for the correction of any submissions made in error.

If, however, you don’t want your sales administrators and channel operations managers to see the Submit for Approval action on approved deal registrations, then create custom job roles for those users with the Resubmit Deal Registration privilege (MKL_RESUBMIT_DEAL_REGISTRATION_PRIV) removed.