Does legacy software equate to uselessness?
Not necessarily, and more so, if its owners have pumped-in large sums of money to keep it afloat. Unless the apparent “uselessness” necessitates a complete shift across systems, a legacy system need not always be dumped in its entirety. That said, there can be a need to shift wholesale when the technology so dictates. Servers for example. At one time, one had to own and maintain them like a holy shrine. And then came the cloud which totally blew away the need to self-own and maintain structures while giving better output under a SAAS-HAAS configuration. The decision may depend upon whether costs first incurred have been recovered and to what extend an existing system can be rejigged to new circumstances.

Has the owner of the legacy system taken its money’s worth?

Systems, legacy, or otherwise are expensive affairs to invest in and keep them up to performance levels. A system should ideally be termed legacy in monetary terms, the owners under a system of fixed amortization recovered its worth and are in a position to re-invest the same in a better system. Financial calculations apart, legacy systems can sometimes be an organization’s most prized possession in terms of money given the amount invested in them, and it could make more sense to invest in its regular upkeep than a complete shift-out. On the other hand, if these are proprietary systems with all resources in-house, the chances of buying/ replacement could be a relatively painless affair.

Is support for a legacy system of a certain quality easily available at reasonable costs?

A system is technically declared a “legacy” where support for its upkeep including timely patches is either not available or can be made available only at excessive costs. Under both these cases, an important system can bring an organization to enormous grief. Important information can either be lost forever or land-up in undesirable hands. It thus makes sense to move on to a new system where the existing one either has no back-up or expensive and/ or unverifiable ones with little guarantee of performance.

Is the use of existing software (the legacy software) dangerous to an organization’s existence?

Imagine the case of a nuclear powerplant operating its reactors on aging platforms which shows or has potential tendencies of slipping once in a while. A truly dangerous situation that should be immediately be rectified either in entirety or at least those parts which can mitigate an outright disaster. Compare this with another software handling the same complex’s canteen needs. Despite being old and creaky, one can still use it because it really does not pose a threat to lives.

What is the level of pain one would feel when replacing a legacy platform?

If the legacy platform forms the central system in an organization or a substantial part of it, enormous pain will be felt if anything sudden is attempted. To reduce the same, it would make sense to first plan out things on a schedule and then take relevant action- if it has to be taken in the first place. Enormous data may need to be shifted from one system to another with the latter taking its own time to settle and respond. The question of re-engineering versus buying may have to take into account what causes less pain, how often, and for how long.

In the end, after asking and answering all the above questions, one should also do the following:

Consult in expert about how legacy platforms can best be handled and if there’s a chance of reviving the element of support- taking cost and time into consideration

Do a thorough study of alternatives available including the use of HAAS and SAAS and other such alternatives that may arise- taking into account costs likely to be incurred and results likely to be derived

Do a study of existing and likely road-blocks and weaknesses within the organization vis-à-vis existing legacy systems and the likelihood of them remaining where an alternative is found.

In the end, the decision is to re-engineer or buy afresh could be a very subjective one given the number of considerations to be taken into account. That said, a decision sometimes HAS to be made. With that being the case, a thorough, studied decision-taking every angle into account ought to be the case. Haste shall otherwise result in substantial waste.