When you say ex pat "labour", do you mean the tens of thousands of mainly Asian and Subcontinental manual workers who do everything from building hotels to working in petrol stations to waving red flags at roadworks? If you do, then I feel that they will never leave until employment conditions (job availability and pay in their own countries improves).
If you are referring to the other tens of thousands of professional people (pilots, cabin crew, doctors, lawyers, engineers, accountants, nurses, shop and retail staff.......etc, etc, etc,), I feel that exactly the same answer`applies. That is why we are all here, in the main.
Dubai is not stupid enough to risk having a mass exodus of ANY of the above two "labour" categories, as its very existance and future depends on these people being here and doing the jobs that they currently do.
Indeed if the ruler's ambitions of doubling the population of Dubai in the next ten years is to be achieved, then there is simply no scope for this to occur through an indigenous mechanism.
I am quite intrigued as to why you have made your initial post - where do you see things going wrong?
AB6