Either way the money lost in recruiting and training them is gone.
I agree. Many times in negotiating salary with a potential employer, the HR people and the Manager do not consider these costs.
A couple of months ago, I was offered a position with a company. When I received the call from HR with the verbal offer, I attempted to negotiate $2500 higher than their initial offer. They did not want to budge even though they were only offering me $2500 more than I was making at my present position. I decided to send an e-mail to the hiring manager stating that if they hired me, the company would save considerable training costs since I already had all of the skills they were seeking for the position. They still didn't want to budge (no reply). I can guarantee you that the person they hired needed at least $5,000 in training for one of the skills required for the job (which is rare in the current market). I realize that the training budget and salary budget are handled separately in most companies, but they weren't even offering the current market rate for my position.
I think there should be a new thread on IT hiring practices. I could tell you a lot of strange stories from both ends of the process.