Research and product testing
If you are documenting something technical, then there is no replacement for getting your hands dirty experimenting with and using a product like an end user might do. This process is easier if you have a technical background or experience, but you can gain that over time, and sometimes, having a fresh pair of eyes can help reveal problems no one had anticipated. In small companies, at least, documentarians are often the first people to try a product or feature after developers, and our position between engineering, product, marketing, and support can give us a unique and broad perspective on a product.
However, I am what I call a “technical” tech writer. I studied computer science. I dabble in programming. I can throw together infrastructure as code and databases quite happily. Don’t ask me to create a large-scale production-ready application, but I know enough to write examples and, crucially, ask the right questions.
Few documentarians...