Despite its strengths, Tally.ERP 9 was not without limitations. Its relational database (TDL, Tally Definition Language) was powerful but proprietary, making advanced customizations reliant on Tally-certified developers. The interface, though functional, remained character-driven and keyboard-centric, which felt dated compared to the mouse-driven interfaces of contemporary software like QuickBooks or Zoho Books. Moreover, large-scale enterprises with thousands of concurrent users often found performance bottlenecks in high-transaction environments.