In general, investors like the businesses they invest in to be incorporated in strong, stable countries with stable governments in jurisdictions with a long history of favorable corporate case decisions. Delaware is the top choice not because it is the most favorable tax-wise, but because of the history of corporate cases tried in Delaware courts. Contrast Nevada, which has somewhat more favorable tax and privacy situations for corporations but a corrupt legal system (hello, casinos). Nobody wants to invest in Nevada corporations.

If you take your startup offshore, where will the court cases happen if things go wrong?