• DoD looks at systems from total lifecycle perspective
• 60-80+% of the lifecycle costs of software occur in maintenance
• Arguments based on lower development costs total only 20-40% of the story
• On most projects, development and maintenance are two separate contracts
• Commercial Off-The-Shelf (COTS) software is not always the correct choice
• Decisions must be made on lifecycle costs not development costs

From the Script: SLIDE 37 - Software Development vs. Software Maintenance

Let's move on to discuss a consideration that makes Ada an even more attractive choice, a consideration that is often overlooked. Because the procurement system contains an inherent conflict between software development and software maintenance, the cost advantage of Ada may not always be clear.

When looking at computer systems from a total lifecycle perspective, researchers have found that sixty to eighty percent of costs occur after development and implementation. The maintenance phase accounts for the lion's share of the costs in traditional projects.

What we find is procurement decisions that are often driven by lower development costs. When you focus on that single phase of the lifecycle, you are only getting twenty to forty percent of the story!

On most projects, development and maintenance phases are handled as two separate contracts. This creates an artificial division in the lifecycle that makes it easy to overlook the costs of maintenance. The savings in maintenance costs is one of the most important advantages of Ada.

Another discovery is that COTS software is not always the correct choice. Maintaining COTS is difficult if not impossible. Source code is not always available. In addition, vendor support does not always continue.

To get a true picture of the costs of a software system, you must take the total lifecycle into consideration and not just the development phase. It is in the best interest of the customer to make a fiscally responsible decision.