One of the reasons why it is not safe for people to eat raw meat is because of the bacteria and other particles that can be found in raw meat. Do you know that E.Coli can survive even if you freeze the meat? Another reason is that you will not get as many nutrients from raw meat as compared to cooked meat.
This is something that you can think about the next time that you decide to get tartare. If the meat is contaminated with various bacteria, expect that you can become ill. There are various diseases that you can get from eating raw meat. Why do it when you can avoid it, right?