If no schools are being created the law is clearly failing. But the evaluation should not stop there. Success is more than just schools-appearing, however. To be 'working' the program needs to produce schools also for regular students. Only if schools appear that are attractive to families the districts want to keep will districts respond with changes and improvements in their own programs.
Quality is important, along with quantity.
In most states where schools are appearing the Legislature has made it possible for more than one public body to be offering public education in the community. So in the important states there will be fascinating questions about the different behavior of the different kinds of sponsors. Do districts when asked to sponsor make different decisions . . . For those who enact the laws it is to create dynamics that will cause the mainline district system to change and to improve. The charter schools, helpful as they may be to the students who enroll in them, are instrumental.