Help wanted: who pays to simplify your IT portfolio?

Entropy creates IT portfolios.  As time goes on, business needs change.  Mergers happen.  Tool strategies change.  It is inevitable that every IT department will find itself (rather frequently) facing the situation where there are two or three or four apps that perform 'important task fourty-three' when the enterprise needs exactly one.

So let's say that important task fourty-three is to "track the number of widgets in the supply chain from distributor to retailer."  Let's say that the Contoso company has two divisions.  One makes toys.  The other makes fruit snacks (a mildly perishable snack).  These two divisions have different needs, and the were built at different times.  Contoso purchased a supply chain application for the toy division, and built their own for the food division. 

So, along comes an architect and he says 'you only need one.'  After the business stops laughing, they ask if he's serious.  When he says that he is, they argue that he's wrong.

Let's assume he wins the argument.

Who pays to combine them?

The needs are different.  The application that manages the toys is not able to handle perishable items and the interesting stock manipulations that go on.  It is not able to track batches, and their due dates.  It is not able to calculate the incentive rebates that Contoso offers to retailers to refresh their stock when they flush aging inventory.

Combining the two may very well mean purchasing a third application and migrating both of the two older systems' data into it.  Or it may mean expensive modifications to the commercial package, or the addition of custom code to the in-house tool.

That costs money.  We want to spend money to save money.  Fine. So who takes it on the chin?  Who extends the credit?  The food division or the toy division?

These decisions are not rare enough to run it up to the CIO at every turn.  There has to be a rational way to fund the decommission of an application, move and archive data, validate functionality, update process flows, re-attach broken integration pathways, etc.  It can cost as much to turn an application off as it did to install it in the first place.

What have you seen work in your organizations? What process do you use?