FactSet Test Automation Engineer interview questions

They will be having 3 or 4 openings for a position and they invite minimum 600 people for interview and they say it as scheduled interview. First will be online multiple choice questions. This one will be done with out much waiting. They announce the results also in 15 to 20 minutes. After that you have technical round. They will have 4 or 5 panels and they need to interview 200 people. We waited for 4 hours after written test. And they told us that they will schedule interviews as there were many people. And they don't call for interviews. Just for 3 to 4 positions, they let wait everyone whole day