They are mostly paid, so do not pay attention to ratings. In general all rating websites are paid, so you can create whatever rating you wish, if you have enough money. Do your own research and do not trust such websites.
Do you mean it is fake rating ?
Yeah most of the rating is fake. Project team pay some money to achieve good rating. I saw few people working on this area.if you search there you will find that top rated ico turned to scam. So dont believe in rating. Better to find out good ico or ieo project yourself.or there is high possibility to scam or you may loss your money.And i dont believe in rating now.