Well, when one is born into this world with a humanity full of hatred (non-compassion and non-love), willingness to kill and greed, and one thinks seriously about how this could be changed, there would come times were one would really doubt if it is possible at all to get humanity to a state where this stops and humanity will be governed by love and compassion. First of all, one would have to be very smart to think of an indded possible way, and second one would have to be aware that there would be many beings who would not believe that it functions and would rather vote for destroying humanity. One would have to be aware that those beings would try to stop any development going into the envisaged direction. And when this would seem to be quite successful at least temporarily, one could easily start to doubt that one could never reach one's goals.