People vote with their feet. We have written before about how 3 times as many people move to Tennessee than Kentucky because of lower tax rates and school choice laws.
Another reason may be that people want to live somewhere they don't have to be forced into joining a labor union. Tennessee is one of 22 states that has Right-to-Work laws which make it illegal to deny employment based on association with a labor union.
You can view the language of Tennessee's law here. Contact your state legislator, they may be interested in seeing an example.