One of the challenges of seeing ROI from SOA is failure to measure. Many SOA projects are launched in which managers don't know how well the initiative may have succeeded beyond anecdotal evidence. It may, for all anybody knows, a raging success. Likewise, how do we really know when an SOA effort has truly "failed"? There need to be baseline metrics of various business impacts or performance indicators to measure progress against.
Loraine Lawson helps provide clarity to the SOA measurement issue, providing pointers to some of the metrics for measuring the ROI of SOA. She points to an article by Leo Shuster in SOA World, who contends that SOA needs to evolve into a business initiative, and offers a list of SOA metrics covering the areas of IT, business and financial metrics.
According to Shuster, the four most critical pieces of information that always should be captured include the following:
- All the services being created
- Cost to build each service
- Integration costs related to service reuse
- All service reuse opportunities
To paraphrase the saying, let's measure SOA, one service at a time.