Why is this happening? And can this problem be solved?
Do you mean the stripes, where you expected bricks?
Without input connection the bricks textures uses the generated x-y-z-coodinates of your object to create the brick pattern. But it only uses the x and y parts. So in z direction these stripes generates.
Add the brick texture to the default cube and you will see!
To handle this, you can either rotate your object accordingly or actually use the inputof the brick texture node and adjust the coordinates by yourself.
Thank you very mutch!
But how can I do all sides of the cube with correct texture?
In that case using the UV coordinates will do the trick:
(given you have a suitable UV. for the cube the default generated will do 
).
Thank you again.