The system is being complete replaced . It is
not uncommon to see homegrown systems for human resource functions being
replaced by COTS systems such as SAP or Oracle Financials.
The release is no longer to be supported .
Sometimes organizations will have several releases in production at the same
time, and over time older releases are dropped.
The system no longer needed to support the current
business model . A organization may explore a new business area by
developing new systems only to discover that it is not cost effective.
The system is redundant . Organizations that
grow by mergers and/or acquisitions often end up with redundant systems as
they consolidate their operations.
The system has become obsolete .
In most cases, the retirement of older releases is a handled during the
deployment of a newer version of the system and is a relatively simple
exercise. Typically, the deployment of the new release includes steps to remove
the previous release. There are times, however, when you do not retire a
release simply because you deploy a newer version. This may happen if you can
not require users to migrate to the new release or if you must maintain an older
system for backward compatibility.