I started writing blog posts about 15 years ago. Interestingly main reasons why I keep writing are still the same they were back when I started. I hope that by sharing these reasons here I encourage more engineers to give it a try.
Writing is like teaching one of the most powerful tools of self-learning. Both force us to organise our ideas and think them through. In verbal communication ideas often get clarified in the course of discussion. In writing we have to be much more disciplined and unambiguous from the start. Hence it is good way to train our mental muscles.
Writing is a great way of sharing our ideas and making people think about the topics that we find important. For example, we tend to use practices and patterns out of habit or due to their popularity. These cargo cult patterns are easy to spot looking at the past but they are less obvious in the present.
Writing gives us another chance to test our ideas. Often when working on a project it is not possible or simply impractical to try out all ideas we accumulate during the course of the project. Writing about them helps us to explore these further. We can use writing as an experience multiplier without having to multiply our effort.