Do not call yourselves a fair interviewing panel if you assume people are going to look at Glassdoor for your interview questions and prepare for them. Change your questions to be actually fair and just for hiring a potential engineer. If you are going to be tossing a coin and assuming someone saw the question and prepared, that is the height of unfairness and biased interviewing and people operations. It is the most biased panel ever seen. Either do not call yourselves unbiased or at least change questions instead of rejecting someone without any basis. Many engineers can have the same thought process and also could have quick grasping power. This is the most prejudiced company ever.

Let me not do that. They've probably just one question. If it leaks, they'll be just randomizing the people they want to reject.