Why is eye color not a good example of dominant and recessive genes?

We discussed it in my biology class but I can't remember what my teacher said. Also the same for hair.Why is eye color not a good example of dominant and recessive genes?
Good examples of dominant and recessive traits are often those traits that result from single genes. These examples are easy to understand and easy to teach. Eye color and hair color result from the interactions of multiple genes, are much more complicated in terms of genetics and don't reflect simple dominant/recessive alleles. Some examples of single gene traits in humans are:





sickle cell anemia


cystic fibrosis


attached versus unattached earlobes


polydactyly