Atari feels good, but it is not always good. Atari, atari! 
Before Black gives atari, White has two liberties and Black has a cutting point at a. After Black's atari and White's extension, White has three liberties and Black has two cutting points, a and b, to worry about.
The following diagram illustrates the problem. It feels good to make forcing plays, but often the result is to strengthen the opponent's stones and to weaken our own.
The hiki of the tsuke-hiki combination is a good shape move.
a is a weak spot in White's formation:
Black can peep there and and kill with b next..
Right: The weakness has been removed in sente and White can now play .
Cases where atari-atari in a different sense, atari followed by atari, is appropriate include
- Beginners play atari.
- Don't atari automatically is one of the 20 principles of Opening Theory Made Easy, a book by Otake Hideo.
- Western squeeze
If a DDK player only played atari for very clearly formulated reasons (to him/herself, in his/her mind). e.g.:
- eventually capturing stones
etc. etc. - s/he might get two stones strength improvement alone by holding back all ataris for which you could not clearly define a reason. (Because many more opportunities would occure, because the opponent's stones would not be settled.)
If atari was given too early - often one regrets later not to have the possibility to give an atari from another side or to another stone.