When talented people write badly, it's generally for one of two reasons: Either they're blinded by an idea they feel compelled to prove of they're driven by an emotion they must express. When talented people write well, it is generally for this reason: They're moved by a desire to touch the audience.
Story: Style, Structure, Substance, and the Principles of Screenwriting (ed. Harper Collins, 2010) - ISBN: 9780062039828