The other day I asked a friend for their blog URL and they did not have a blog. I was shocked. I thought every intellectual has a blog (or some other outlet) nowadays, but I was wrong. Because having a blog is such an obvious thing.
Blogs have several properties, which make them a good choice in many instances. And since you read this on my blog, I have to assume you might have sufficiently interesting things to write about, so this is the first reason why you should write a blog.
Blogs are cheap and hard to monetize
A blog does not need much to run.
Ideally you host it yourself and use some file based backend, because this makes for even easier backup, but e.g. when you're a student or have no other income, this might be prohibitively expensive.
But there are thousands of free ways to host a blog, e.g. github or gitlab pages and if you do not use something like WordPress, migrations are easy and you can probably run your blog at close to no cost forever.
Furthermore, the golden era of blogs is over, and nowadays "starting a blog" is nothing anyone considers a business model anymore. It probably can still be profitable, but if you were to create a business, you would not choose to start a blog anymore, but probably some kind of niche landing page with affiliate links.
Not only does blogging itself not work well as a business anymore, but also it is not that great of a sales funnel, as those have basically shifted to video platforms. 
Being cheap and non-commercial does have several benefits:
- there is little pressure to create new content, as nothing is wasted, which can increase the signal-to-noise ratio
- it's easy to take breaks or even suspend it when you are not actively writing anymore
- you have fewer incentives to write bad content, like unnecessary product reviews or incomplete teasers to upsell for your coaching or educational program or whatever
- there is not really a cost associated, so you have the freedom to play around with things and can post things you are not totally sure about
Last but not least, being cheap is nice by itself. I am tired of paying.
Blogs are low friction
You can just write a post and it can stand for itself. With stuff like tags you even can get some rough automatic categorization of your posts, and then just adding a simple list as archive makes for a pretty pleasant retrieval experience. No fucking searches, no fucking non-linear timelines, no fucking recommendation engines.
Also you do not have to put in much effort to bundle everything in a cohesive package. To write a long thesis or book, you have to put in a lot of work to make it flow smoothly and make it a pleasant experience, besides having enough to say on a given topic to fill a book. Which most people (including book authors) don't, resulting in many books that should have been blog articles and are only filler fluff, repetitions and repetitions.
Something similar could be said about more traditional homepages. Blogs are more like a pile of stuff and you can just pick whatever you like. However, when you do not really have a singular focus, you end up with many many subcategories, and it is cumbersome trying to reconcile those in a more structured approach.
Blogs are basically object stores, where you have content and some metadata to retrieve it. It's easier to scale than file systems, where things have to be hierarchical in some sense.
And if there really is a cohesive topic, you can always just gather all the posts belonging to it and create a miniseries or put those things on a separate page.
Blogs have a preselection
With blogs, your audience builds organically and unless you make it to hacker news, there is very little influx of inconsiderate people. You can assume a little bit that readers will get accustomed to your writing style and lingo, and more importantly, you can assume any level of competency you like. Your blog can be very basic, or you can work with very abstract foundations. You can be more nuanced, as you can expect your audience to understand quantifiers and their implications.
You can get pretty much right to the heart of the matter, if you like, or at least you do not have to preface every post with a introduction to Bayesian statistics or an overview of the von Neumann architecture just because you want to talk about clusters of computers.
Also, you do not have to convince the reader, which is another reason why many books exceed the appropriate length by far.
Blogs are easy to backup and maintain
Preserving knowledge is one of the largest challenges we face. The times where the internet did not forget have been. Proprietary services are very forgetful, often on purpose. If you can not download it, you have to expect to never see it again. Often you even can not start a series anymore before it gets pulled from the respective service.
Blogs on the other hand, are easy to backup. It's text. Everyone can download it. Usually you can simply print it to PDF, even though for proper rendering there people should put in more effort than I did. If your source is some repository, as a blog owner you can keep it around pretty much forever.
Blogs are great filters for yourself
I do keep around almost all the posts I started writing, even though some of them never finish. Often for a good reason: Once you start writing things down, you notice when things just don't sound as nice as they did in their head.
Keeping old drafts around is nice though, because sometimes you find out why an idea was actually bad and then you can finally let this article rest. Or you sometimes find the reason missing that tied everything together.
I do have a pretty good memory, so in general I remember most of my good and bad ideas, but I do not remember exactly when I had this idea, or in which context. Having a file which is roughly dated then is not only a nice reminder, but I find it also interesting to see how much or how little one has learned in the mean time, and just having some understanding of how long it takes for oneself to discover things makes learning new things easier to plan out.
|Obviously I have no idea about these things, lest I would not be poor, but I digress. Video content is just much more wasteful^w engaging per unit of information and people on which sales work are much more likely to be influenced by video