Why do people think the assassination of cesar was such a bummer?

A bit off topic. This may be the wrong forum as well, but some of you all seem to have a grasp on history. Why was it considered such a tragedy? I mean, I hear he was kind of a bad guy. Perhaps I should study ancient Rome a little more, but I would like to hear your opinions on the topic. So thank you very much if you have some input. All opinions are welcome.