Why do people complain about everything?

I think people complain because they want people to to be interested in what they feel is tribute to their life. But I'm personally tired of it I work in higher education and i must say I have never seen so many people that won't help themselves first. Always complaining about what they got to finish and what they didn't do because they didn't put in the time and effort to finish anything. Get over it please!!! Just do what you got to do. Don't expect everyone to help out some things you must do on your own.