Many obstacles can prevent a person from completing creative work. The first major obstacle is lack of necessary skills. It takes many years for a person to develop skills to a level where they can be used without conscious thought, and yet you cannot be creative until skills are so well assimilated that they become instinctive. The next major obstacle to creativity is lack of time. Although some famously disciplined creative writers work best around full-time jobs -- Wallace Stevens and Anthony Trollope are famous examples -- in general having time to focus on a specific project enhances the chance of creativity. Finally, one needs a social environment that allows freedom of expression.