Is it right to quit a contest after seeing the problemset and feeling that you can not solve them?

Or is it necessary for the platforms to introduce some kind of system such that only the contestants who are participating can view the problems?

Recently Atcoder has implemented Rated/Unrated participation.

I don't know what the reason may be, but I feel those who are participating unrated can do that with virtual participation also. It is like playing friendly matches in the middle of a World Cup.

What do you think?