The first year of school

In my book called Beginning Reading, the first couple of chapters talk about starting the first year of school. One part mentioned that in the first day of school you can already tell which students are going to succeed in reading and which ones are going to struggle. It said that children who come into kindergarten with poor literacy and comprehension skills, are already behind from where they are supposed to be. I understand that when children start kindergarten they should already have some prior knowledge of literacy skills but there is no way to ensure that all children starting kindergarten have that prior knowledge. I am not sure how I feel about this situation, not all children get to attend some sort of head start or pre-school, and I don't know how we can expect children to already have so many literacy skills when they have not been properly taught. So when they start kindergarten and they have not had the opportunity to be taught such literacy skills, it is as though they are being set up for failure. The good news is that when they do start kindergarten they will be presented with the opportunity to learn such skills we just hope that they are resilient enough to catch up to where they are supposed to be.