Oh, I was not specific enough. What I wanted to write is that a habit of swearing is harmful to your social skills after you leave the school. Imagine a person at a job interview saying: "Yeah, I know the fucking Java, but NetBeans is gay, and if you ain't doing unit tests like all the time, you are seriously retarded, man." ;-)

Probably no one would do this intentionally, but the problem is, if you get a habit of swearing, then sometimes a word or two slips through, often unnoticed (by you; but your audience is shocked). At some moment this happened to me (no, not at a job interview, at least I think so), and after getting a feedback I decided to be extra careful. Which I would want to teach my children. I was very lucky to get that feedback, because most people assume that others are well aware of all the words they use.