Oh I think part of it is how you think of “dominant” and “recessive” alleles. I feel like I was taught that dominant alleles mask the recessive allele - so in other words as a random example that the allele for brown eyes is dominant and the allele for blue eyes is recessive, so if you have just one copy of the dominant allele it will hide the blue eyes trait. Often that’s not what happening - really the dominant allele makes a functioning protein while the recessive allele makes a protein that is “broken “ and doesn’t do anything. So the recessive phenotype is really the result of not having the functioning protein at all. Obviously there are tons of different scenarios, but a lot of genes do work this way.

I have no idea if there is really a gene for blue and brown eyes but using that as a hypothetical example: the dominant allele that gives you brown eyes would really be making a protein that does something with pigment that turns your eye color brown. Without that protein doing it’s job your eyes would just be blue. Having one copy of the allele that makes the functioning protein will make enough of it to turn your eyes brown, so it’s “dominant”.