When the head of a project which has already run tens of millions of pounds over budget - and is running

years late - leaves, it is far from reassuring.

If that project has already suffered disastrous launches and is rapidly approaching another crucial deadline, alarm bells should surely be ringing.

It is true that when Ian Crichton took over from John Turner, the previous chief executive of NHS 24 in August last year, it was only ever seen as an interim appointment. But many must have hoped that Mr Crichton's experience as head of NHS National Services Scotland, would be ideal to help see the troubled helpline through to the revised launch date in June.

The bungled IT upgrade, known as the Future Programme, has become yet another dismal example of poor Government IT procurement, with costs having spiralled from a predicted £75 million to a likely £125 million. Concerns from staff - who had not been given enough training - and from other health boards led to it being dropped a few days after it was first implemented, with helpline workers told to use pens and paper before being told to go back to using the old system.

The Future Programme is intended to deliver a more streamlined, coherent and cost-effective system , although many of the intended savings have since been undermined by the need to keep paying the running costs of the previous call-handling process.

Is it the case that Mr Crichton's departure for the private sector was always expected? Or is there more reason to be concerned, given the lack of explanation? It is notable that there was no suggestion he would be going when he appeared before the Public Audit Committee at Holyrood, to reassure them that lessons had been learned, on January 20th.

The public have only two interests in this matter. The first is the paramount importance of patient safety and the second is that costs to the taxpayer are kept under control - at a time when other parts of the public sector are experiencing swingeing cuts.

One might have expected Mr Crichton, having taken the helm at a time of crisis, might have stayed to see the crisis through. Yet he leaves with the call-handling IT system not in place, no firm go-live date, and no guarantee that the system will ever work.

This is one of the issues that makes the history of public sector IT systems so problematic. If senior figures are readily lured to the private sector, expertise is lost. Experts in health, justice or tax, for example are not often also experts in IT or in negotiating strong contracts.

Creating bespoke systems for handling large amounts of public information can make it difficult to fix or upgrade individual elements.

There may be nothing untoward about Mr Crichton's sudden departure, but it was notable that he told MSPs the problems so far had been 'systemic'. If deeper concerns about the future of the Future Programme lie behind his move then NHS 24 - or Mr Crichton himself - should tell us.