Michelle Rhee was fired because she neglected to keep the parent's of students informed as to the who's, what's, and why's of her programs. A simple explanation of her goals and methods and a few community forums would have served her well but instead she took on an air of doing what is best for people with little to no reaching out to them as if they were the children and created a nasty backlash because of it. Also, look in to the charges and controversies surrounding the turn around in schools and lack of justification for many of the firings.
Vouchers are a bad idea to those whose kids will be left behind in a crappy system. It may be selfish but wouldn't you as a parent rather have them fix the system your kid is guaranteed to in to?