Where scalability becomes an issue with an existing system, this is sometimes to do with a change of focus. This was the case at Equity Bank in Kenya, which shifted from being a building society with a focus on mortgages to microfinance, with the resultant increase in customers and transactions stretching its old Windows and SQL-based core system. Webster Bank in the US needed a new system because of a fundamental shift in its business,
moving from being a traditional savings bank to a broader commercial bank. Arguably the biggest change of business model of any of the banks in these case studies was Bank of Queensland, thereby necessitating the replacement of its in- house Fujitsu mainframe-based system.
While played down, cost is mentioned by a fair number of banks. UnionBank of the Philippines is fairly typical in that it came to struggle with the total cost of ownership of its mainframe-based core system. This bank also hit a common situation with legacy packages in that it ended up on an old release, several versions behind the current version, so was looking at a major project, whether it upgraded or chose a brand new system. That its branch system ran on OS/2 reflected the fact that banks can sometimes end up down a technical dead-end.
