Architecture implemented in the 1980s is stalling software use with new system design needed to make better use of CRM.
Andrew Purcell, Unisys Global financial services partner said these systems are suffering from "customer interface complexity".
Purcell added Australian banks need to change from an account-centric model to a customer- centric model within the next two years in order to stem the complexity.
"We are not talking about re-engineering everything, just what we need to do which are the customer-facing elements," Purcell said.
"The focus in previous decades was on operational excellence rather than customers; systems that work well don't necessarily service the customers; investments are being wasted."
Purcell estimates that in Australia banks have already invested between A$7 billion (US$5 billion) and A$10 billion on core systems.
Gerd Schenkel, National Australia Bank (NAB) customer strategy and cross-marketing general manager, said the application and exposure of CRM within the NAB has "revealed opportunities for changing the core systems to capture new data to support the expansion of CRM functions".
Schenkel said the main issue for the bank was aligning production schedules to feed data into the CRM system. To do this, core data source systems had to be modified, he said.
While data quality was sufficient when implementing CRM, Schenkel said production schedules for core systems were modified to ensure processes were in place to deliver information at the start of the next business day.