I'm sure each individual would have different reasons for staying in an NHS role or moving over to the 'Dark Side'. Some would be attracted by higher wages in the private sector, but put off by travel or the possibility of having to work longer hours. Not forgetting the public sector pension anyone with a few years service is unlikely to want to give up.
Breeding your own engineers may be one option, but training someone doesn't mean they won't be enticed by other employers - public or private sector. Gone are the days of working in the same department for 30 years+.
Do you only want experience, or are you trying to recruit a certain type of individual? Having experience doesn't mean you'll get a proactive, dedicated worker - there are a lot of people with experience sitting back waiting for a pension!
Perhaps you need to have the flexibility in your recruitment policy to offer specific enticements for certain roles or to target individuals with whatever they want (within reason of course!).
