The rapid evolution of technology creates a high probability that at least one of those components will need to be changed years or even decades before the system itself will be retired. Such hardware changes can, in turn, trigger a need for developers to migrate system software to a new technology to ensure continued serviceability.
The migration to a new technology can be a costly, risky process that developers should avoid whenever possible. But in some cases, it is desirable for financial or inescapable reasons because of hardware obsolescence and new requirements.
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