Computing reported recently on the Department for Work and Pensions’ (DWP’s) ambitious plans for yet another child maintenance payment system (IT revamp to boost child support, www.computing.co.uk/2225797).

Apparently the last attempt cost the taxpayer £450m and resulted in the Child Support Agency (CSA) failing to collect £3.5bn in outstanding maintenance payments.

The proposed new wonder system will only cost the taxpayer £50m – a bargain if it works and the cost does not escalate when it eventually arrives in 2011.

Why is it so cheap? One of the reasons given is that the system will be operated by the newly formed Child Maintenance Enforcement Commission (CMEC), rather than by the system provider. Having spent time analysing the previous CSA fiasco, I do not believe that such economies will be available to the CMEC.

Obviously, I have not seen the business case, but I can just about guarantee that it will not accurately reflect the true cost of ownership of such a system.

We all know that the lifetime costs of any system generally follow the 20:80 rule – 20 per cent of the cost for development, 80 per cent of the lifetime cost to support and extend. Despite this, we continue to see business cases that reverse this experience and blissfully purport that the development costs will be 80 per cent of the lifetime cost of ownership.

This dubious practice is a disgrace that needs to change now. Until it does, we will continue to see unexpected cost and disappointment as the most likely outcomes.

Colin Beveridge