Common mistakes in documentation include mixing content types, unclear audience targeting, and quality issues, such as spelling errors, with a tendency to use documentation as a band-aid for product problems. Applying the Diataxis framework, which categorizes documentation into tutorials, how-to guides, explanations, and references, can help maintain clarity and align content with user needs. Understanding the target audience is crucial, as trying to cater to multiple groups often leads to unsatisfactory compromises. Attention to detail, including spelling and grammar, is important, as errors can undermine trust, while a clean and organized design enhances user experience. Documentation should complement well-designed products, rather than serve as a substitute for addressing complex workflows, and success should be measured using both qualitative and quantitative feedback. Ultimately, strong documentation supports sales by building trust and credibility, and it requires continuous refinement to effectively aid users and support company growth.