Some parents choose to homeschool based upon the quality of education available to their child in the public system. Lower-income counties may not have up-to-date textbooks or school supplies that a parent thinks are necessary for a successful education.
Parents who believe in creation, as opposed to the theory of evolution, will want to pass along that belief to their children. Most public schools present evolution as fact, and do not allow the presentation of creation.
Not all children learn in the same manner. Homeschooling allows parents to tailor the school day to the student's preferred learning style, such as performing experiments as opposed to reading all day from a textbook.
When children are at school eight hours a day, parents get little interaction. Homeschooling allows quality time, built upon learning and sharing new skills together.
Homeschoolers can easily adjust schooling around illnesses, family emergencies or vacations, without the need to check school calendars.