This is because some people wants to take part (and we dunno what their level is).
There're some hard problems but not so hard like this one.
Plus, this is starting, and the level of problems must up slowly.
In fact, I forgot to mention: Do not post Olympiad problems.
This is an IMO problem. You are right, it is not right to post such hard problems.In fact, I forgot to mention: Do not post Olympiad problems.