Bots make curating a lot easier. Everyone wants to get good curation rewards so they tend to curate the highest paying authors with Bots. Of course having those authors get Bot votes means that they will continue to be even higher paying authors. Pretty much all of the high paying authors get Bot votes from people that are trying to do curation and therefore they end up in a never ending circle that results with the highest paying authors getting the highest votes and the lowest paying authors not getting any bot votes. In this respect it is an unfair system but nothing can really be done about it as far as I can see until you manage to become at least somewhat of a established author.