[polyfractal]

I can think of a number of reasons.

-If you make hard-goods, being closer to your manufacturing may be helpful

-Cheaper staffing/skilled labor in non-US countries

-Cheaper cost of living elsewhere

-More corporation-friendly tax regulations

[8bitpal]

Rationally those are compelling reasons for a business to leave.

But I think personal reasons play a huge role in this decision. A majority of the people tend to only leave when the situation becomes unbearable (or not even then).

What would it take for you to leave your home country/area?

I guess it's hard to say until it actually happens. One reason for me to leave would be an oppressive government, I guess.

[ark15]

I would add 'Visa issues' to that list that applies to people who are itching to start companies in the US after being here for 5+ years but cannot due to visa restrictions.