One of the rarest and most under-appreciated skills in tech is the ability to explain things. As an industry, we mostly focus on building and selling, and the twain don't always meet. Many of the builders have deep and excellent understanding of the tech they work with; many salespeople are excellent at persuading customers to do x. But there's a very important and underused bridge between insiders who understand, and everyone else. Blogging is a great exercise for deeply technical, because it's a chance for them to actively ask themselves: What do others not understand, and how can I explain it clearly?