Nissan Technical Centre Europe interview questions

Invited to an open day in Milton Keynes after a short teams interview with a member of HR (Roisin was lovely btw). Thought I was to be on site at NTC but was invited to a hotel in an industrial park. Day was fairly pleasant. went through a presentation about the company, the grad schemes & placements they provided and had two group tasks on the table. All of it was fairly pleasant. It comes to lunch provided and then waiting around for interviews. I understand that such a large company has to go through a lot of applicants, however, making someone wait 4.5 hours for an interview to be the last one of the day is ridiculous. By that time, I must've burnt myself out with anticipation because that interview went down like a lead balloon. A possible way this could be reduced is to tell applicants when their interview is, so they can go off and do their own thing.