But say you did attend the school. Would you want to attend all 7 years and 'graduate' -- take those nasty NEWTs and continue on in a field of your choosing? Or would you take your OWLs and depart -- perhaps to start up your own business, like Fred and George Weasley?
A google search (OWLS Hogwarts) shows, in part
So what kind of career would you want to pursue, when you left school? Would you leave, even before taking your OWL exams? (Remember that OWLs are sat in different years of schooling, depending upon the school!)An Ordinary Wizarding Level (often abbreviated O.W.L.) is a standardised subject-specific test taken during Hogwarts School of Witchcraft and Wizardry students' fifth year, administrated by the Wizarding Examinations Authority. The score made by a student on a particular O.W.L. determines whether or not he or she will be allowed to continue taking that subject in subsequent school years, and whether they might be successful in obtaining a particular job.
As well as referring to the test that students take in their fifth year, the term "O.W.L" also refers to the type of class, i.e. the level of difficulty of the class the student is taking. In addition, "achieving an O.W.L" is used to refer to a class in which the student has passed their O.W.L exam (example: Harry Potter received an O.W.L. in Transfiguration by attaining a passing grade on the O.W.L exam for that class.)