Not sure what the answer is in these cases, because it's far from unique. The top people are almost always employed on detailed contracts, which specify what they're supposed to do, how and to what standards but also what they will be paid in compensation if they're persuaded to leave early. And the maintenance guys were correct: they'd have been out on their ears if they'd failed as badly. But if the accepted wisdom - that you have to pay very high amounts to get the best people - is correct, then what happened in this case?
A very good point, and one that has affected me personally in the past. (but in a different way)
Basically, when I was leaving my last employer to come to live in Llandudno, a 'rumour' circulated that I was actually going to work for a competitor in Manchester.
This was completely untrue, and I told my employer as much.
However, the CEO, and the HR department decided I should be given a large sum of money if I signed an agreement NOT to join the competitor.
I was only too pleased to bank a cheque for agreeing NOT to work for a company who DID NOT want me to work for them in the first place!
I think my point is, issues like this seem to revolve around the incompetence of management, coupled with the easy access to sums of money to make problems go away, without actually tackling the problem itself. Weak management?