At first glance, a customer portal looks like a frontend topic. In practice, however, its value stands and falls with the same questions as any process-adjacent enterprise solution: Who is allowed to see what, which data is authoritative, which processes must remain traceable?
It becomes particularly interesting when desktop applications, back-office processes, services, and web access use the same data foundation. Then it is not enough to build an attractive interface. Roles, approvals, API boundaries, and versioning logic have to work together.
If this connection succeeds cleanly, you don’t end up with a parallel secondary system, but with consistent access for customers, employees, and administrators. This exact point later determines maintainability, security, and extensibility.