Think about what one tax return or one monthly close actually involves before any accounting happens. Request the bank statements. Remind the client. Remind them again. Download whatever lands in the portal, rename it, file it in the right folder. Key the transactions into QuickBooks or Xero. Check the coding against last year. Watch the deadline creep closer for the clients who still haven't sent anything.
None of that is why anyone joined your firm, and none of it needs a person anymore. It needs a system that never forgets which client owes which document and never gets tired of asking.