It was never intended that all charter schools would be successful. As charter school expert Caroline Hoxby points out, the charter concept anticipated that some of the imaginative models adopted in individual schools would not work out for kids.
According to the Center for Education Reform’s Annual Survey of America’s Charter Schools (requires free registration), as of the 2009-10 school term, 742 charter schools had closed, but 5,042 were operating. So, of the 5,784 charter schools that were opened in the US, about 13 percent were closed. Most of those closed because they ran into fiscal problems.
In comparison, in Kentucky no regular public school has been closed, to my knowledge, due to poor performance.