This might be done, for example, when the first player believes that an opponent has an inferior hand and will not Call a direct bet, but that he may attempt to Bluff, allowing the first player to win more money than he would by betting straightforwardly.
Of course, if no other player chooses to open, the betting will be checked around and the play will fail.
While it is an important part of poker strategy, in some home games and certain small-stakes casino games, this play is not allowed. It is also frequently not allowed in the game of California lowball.