i spent much of today listening to music, which is just an awkward segue into what i actually want to say since i spend most of each day listening to music. it's an easy claim that most songs are sad, but it's kind of a surprising fact. it's hard to think of another method of entertainment which is sad; movies, of course, usually have happy endings, as do tv shows, books, and video games. yet most rock songs (taken all-encompassingly) are about some sort of sad unfolding of events, usually but not always romantic.
i probably don't need to supply anecdotal evidence to convince you of this fact, but i will insert here that out of the last 20 songs chosen randomly from my playlist, 14 are obviously classifiable in their lyrics as sad songs, while four can be described as happy and two are more or less neutral. (not counting the instrumentals.) but wait, there's more.
the really odd creature is the common occurrence of the song with happy or neutral music and sad lyrics. these are all over the place; eight of those 14 fall into that category. this is certainly not because a lot of music sounds happy; it can be as simple as minor-key versus major-key, and most bands are certainly capable of writing sad music, as evidenced by the fact that they occasionally do.
it's a very strange phenomenon. my theory is that it is market-driven. people don't want to be depressed by songs; they don't, for the most part, want sad, languid music. yet we look to music for friends in a way that we don't to movies or books or television; because there is only one character (most of the time), it draws our full empathy. so we expect something we can relate to from the words, since the one-singer approach puts us squarely inside the protagonist's mind. even though other people are depicted in the words, it is one hundred percent through the eyes of the singer.
in addition, because we never see any of the described people and objects, our minds are free to put whatever is relevant in our own lives into those roles. this isn't the case in movies or tv, where we are given a very detailed physical image of the other characters, or in books, where the description is usually explicit. rather, in songs, we are given descriptions of other characters primarily through their actions instead of their personality. it's much easier to project these actions onto people we know than it is for personalities.
obviously these tendencies are not absolute; after all, there exist plenty of sad songs, happy songs, and even the (very) occasional song combining sad music with happy lyrics. nonetheless, given that at least 90% of movies, tv, and books is devoted to at least happy endings, the number of tragic songs stands out.