Where does the significance (Bedeutung) of an IAM system come from?

From the benefit it brings to the downstream IT systems and processes it supplies: IAM has no value of its own, only through what it enables elsewhere.

Nobody buys IAM for its own sake. A user does not want to "use the IAM"; they want to read their e-mail, file an expense report or run a machine. IAM matters because the downstream systems (nachgelagerte Systeme) it supplies with identities, authentication and permissions can then work securely and efficiently.

This has two practical consequences:

• Measure IAM by its consumers. The value of an IAM project shows in the applications it protects, the processes it speeds up and the audits it passes, not in the IAM system itself.
• Design IAM as a shared service. The Swiss IAM design principles (eCH-0107) recommend that applications use decoupled IAM services rather than building their own login, for reasons of cost, modularity and extensibility. The more systems an IAM supplies, the larger its benefit.

This is also why the argument for an IAM budget has to be made in terms of the business it serves (see the card on stakeholders in practice).

Go deeper:

• eCH-0107: design principles for IAM — the principle that relying parties should use IAM services decoupled from themselves (in German).