Tech Mahindra interview questions

I was contacted by one of Tech Mahindra's representatives for a project at their client location. I was told (in her words), "Your profile is screened and shortlisted by Tech Panel for f2f customer discussion. So, probability of selection is very high." But once I reached there, there were several candidates representing even other companies. In fact, even the Client at whose location the interview was scheduled also was blaming the Tech Mahindra rep. for not actually screening candidates and getting in candidates with profiles not relevant to their requirements. This was highly unprofessional of Tech Mahindra to waste the time of both candidates as well as the client. I was asked to leave as the client's interview panel couldn't handle the number of candidates present, and was told that they would call later for a telephonic interview. As a result of this unprofessional behaviour by Tech Mahindra, I lost an opportunity with another leading IT firm with whom I had an interview scheduled on the same day.