The primary reason that clouds rarely form in the stratosphere is that

The primary reason why very rarely clouds form in the stratosphere is that the amount of moisture that reaches the stratosphere is very small, in most cases too small for clouds to form. The temperature in the stratosphere is slowly increasing with the altitude, so it does not cause convection and it has a stabilizing effect on the atmospheric conditions in this region.

It has the potential to lead to limits on rights by giving flexibility in making laws.