Is Service Reuse Overrated as a Value Proposition for SOA?

Yes, SOA reuse is highly overrated.

When SOA first started climbing up the hype cycle, it was pushed to developers as a way to increase the "reusability" of their code by making everything into a service. This created at least two problems with the first being a massive service proliferation as developers eager to jump on the SOA bandwagon made everything into a service, which in turn led to poorly performing architectures (not SOA's fault) and huge issues around service management and governance. The second problem was that upper management and the mainstream media also started "drinking the reuse Kool-Aid" served by the bottom ranks.

The fact is that reuse is only a by-product of SOA. Adopting SOA for reuse is like saying that you're working out to sweat (instead of for losing weight, building muscle, or improving overall health). In fact, I would contend that the re-use provided by SOA is only marginally better than what we've had in previous architecture generations. We've gone through libraries and modules in procedure-oriented architectures, objects in OO architectures, components in component-based architectures, and now servces in SOA. A key issue around reuse is not the technology but the identification, segregation, and granularity of "reuse" items - none of which are dependent on what architecture style you are using. The real value of SOA is as a building block of the larger enterprise-level strategy of aligning IT with the business to ensure that IT value is justified, IT supports the business objectives, and IT has an equivalent level of agility to adapt with changing business needs. In some cases, SOA even becomes the catalyst that spurs the IT alignment to business objectives.

In a nutshell, SOA is about strategic IT alignment with business goals and objectives. Service reuse is only an operational - not even tactical - outcome of SOA. A corollary to the discussion is that many bottom-up adoptions of SOA start with lofty reuse objectives and either quickly become disillusioned or fail to demonstrate adequate value to the rest of the organization because their original reuse goals are far from being met. That is why SOA has the best chance of success with a top-down adoption with the long term sight on strategic alignment objectives rather than operational reuse objectives.

Originally posted on the ebizQ SOA Forum on September 18, 2009