Off-the-shelf components still need attention

Typical advice for the builder of a system is often "when possible, use commercial products". The idea is that a commercial product is more stable, better maintained, and cheaper in the long run.

Today, that advice might be amended to "use commercial or open source products". The idea is to use a large, ready-made component to do the work, rather than write your own.

For some tasks, a commercial product does make sense. It's better to use the commercial (or open source) compilers for C#, Java, and C++ programs that to write your own compilers. It's better to use the commercial (or open source) word processors and spreadsheets.

Using off-the-shelf applications is a pretty easy decision.

Assembling systems with commercial (or open source) products is a bit trickier.

The issue is dependencies. When building a system, your system becomes dependent on the off-the-shelf components. It also becomes dependent on any external web services.

For some reason, we tend to think of off-the-shelf components (or external web services) as long-lasting. We tend to think that they will endure forever. Possibly because we want to forget about them, to use them like electricity or water -- something that is always available.

Commercial products do not live forever. Popular products such as WordPerfect, Lotus Notes, and Windows XP have all been discontinued. If you build a system on a commercial product and it (the commercial product) goes away, what happens to your system?

Web services do not live forever. Google recently terminated its RSS Reader. Other web services have been born, lived, and died. If you build your system on a web service and it (the web service) goes away, what happens to your system?

Product management is about many things, and one of them is dependency management. A responsible product manager knows about the components used within the product (or has people who know). A responsible product manager keeps tabs on those components (or has people who keep tabs). A responsible product manager has a plan for alternative components, should the current ones be discontinued.

Leveraging off-the-shelf products is a reasonable tactic for system design. It can save time and allow your people to work on the critical, proprietary, custom components that are needed to complete the system. But those off-the-shelf components still require a watchful eye and planning; they do not alleviate you of your duties. They can fail, they can be discontinued, and they can break on new versions of the operating system (yet another off-the-shelf component, and another dependency).

Build you system. Rebuild your legacy system. Use off-the-shelf components when they make sense. Use external web services when they make sense.

Stay aware of those components and stay aware of their status in the market. Be prepared for change.