Blitz chess is a five-minute game, during which time both players would strive to put his or her opponent in checkmate. Either that, or hope that his or her five minutes would run out. Obviously, it doesn't really leave much time for proper planning of your moves, in comparison to other games of chess that are considerably longer than blitz. As a result, there are bound to be more missteps made. So what exactly are the benefits of playing blitz chess?
Quicker reaction time
I do believe that blitz chess is a means of improving one's ability to recognize certain chess patterns and respond accordingly to them. That said, doing so would also require an exceptional skill at observation on the players' parts in order to make the right move, such that you would not easily overlook traps set by your opponent, especially in your haste to finish the game.
Mastery of Tactics
In order to place your opponent in checkmate as quickly as five minutes would allow, all your efforts will be spent more on looking for the best possible combination of moves to that effect than finding strategic points on the board. In my experience, as blitz games do not usually enter the endgame stage, where both you and your opponent would be left with only a few pieces, material advantage doesn't really weigh much on the out come of the game, more often than not, especially when you take into account the number of idle pieces on your opponent's side of the board.
Another thing to point out is the fact that winning combinations would sometimes involve a piece sacrifice, which reiterates my point about the irrelevancy of material advantage in blitz chess. In my case, I usually would perform a sacrifice if I'm unable to move the piece being attacked to a safer spot, one not likely to be attacked in the next few moves, usually to break through the opposing king's pawn defense.
I wouldn't recommend any beginner players to try blitz chess if you haven't yet seen much in the way of thirty-minute games or longer. Also, it may seem unfair to lose a game by running out of time, more so when all your pieces are lined up for the win and you have only a few seconds to spare for the last few moves. I do agree with the suggestion that one should maintain a balance between blitz and longer games, as letting oneself indulge more in the former has the effect of encouraging a leap-before-thinking mentality on the player's part, which can be especially dangerous in longer games if one does not know where one would land. As cliched as it would seem, it is worth mentioning that slow and steady wins the race. Unless, of course, it happens to be a five-minute race.