It has happened to some people going for interviews without having prepared and done their research about the company that they want to work for. It's very important to know that working for a private company is very different from working for a public company.
Information about any of the government departments is easy to find or easily accessible unlike that of private companies which will require you to go into their web site and do your research. Having said that, it is sometimes difficult to find information about a private company.
This reminds me. Late last year, i went for an interview at one private company. I was not prepared as i was called unexpectedly and never thought i would be called by such company. Because i was offered the job over the telephone, i could accept whatever they we telling me, irrespective of how attractive the offer was. But, eventually, i set up an appointment to discuss the job offered. Having just completed my second year that year and was going to do my third the following.
I did research as for whether certain institutions would credit me if i was to complete my degree with them. Unfortunately, they would not and i would have to re-do my second year.
During the second interview, in fact after being interviewed - i was asked if i had anything to say. Sadly, i told them to withdraw me on the interview candidates as i would rather go and finish my studies first and then start loking for a job. They(the panel) were not happy with my decision and were kind of saddened by it. They were, however, understanding and promised to keep my profile with their HR Department in case of future job opening.
I realised that at least i am employable. I didn't get to do much reach for my interview but i just knew a little if not much about the company.
I must say this - it was a very interesting company to work for - i even felt like i worked there already. And to tell the truth, i do miss the place though.
I know i should have done an intensive research - now because i know of what i should have done - do you proper reseash on the company you want to work for.