Compass has higher tuition than the other schools in Qatar, so some families probably did leave to attend ACS. Others wanted the American Curriculum and couldn't get in to ASD, so when ACS opened they moved over. There are loads of reasons that there was movement to ACS from other schools. 

There will be happy parents/students and unhappy parents/students at any school, and *obviously* there will be movement amongst schools when something new comes to town. I can only imagine what would happen if DESS and ASD were to open additional campuses. 

Each parent has had their own experiences at their respective schools and each of them has a right to form their own opinion, but to label the school as categorically "horrible" seems to be a bit much. . .