There are many reasons someone might be unable to write (blogs, reports, papers, etc) even when they feel the direct motivation to do so. For some, anxiety produces doubts about the writing process which causes a response of inaction to avoid the stress of writing. Other can struggle with the executive dysfunction that comes with ADD/ADHD, stress, depression, and mental health concerns. I'm not really able to speak further on the why your brain just won't let you do stuff, but I can share the coping mechanisms I found that help me write.
1. Do not strictly hold yourself to content-based goals
It's very intimidating to say "I need to write this paper today" or "I need to upload content today". Now, if you don't mange to finish the paper or post, you've automatically failed. There may be many reasons why the quality of your work produces more or less content each day, so this may be an unrealistic goal to try to control for in saying "I will do X today". I recommend 20 minutes. Committing 20 minutes to doing a task is very reasonable and even my anxiety sort-of understand that this is a reasonable ask, so I break it down into something I can handle.
2. Create and save many drafts
When wanting to create something, set out to create a few different drafts. For example, if you're trying to write a 2-5 paper for an assignment, start by writing the first few paragraphs of a mandatory section (like the literature review or background sections). Write when you have an idea without judgment and save it away for later. At a time where you need to write, go back and either use your original writing, or write a reaction to it, as if you were responding to yourself.
I wrote this post like that, I wrote about 40% of the content and got distracted. Instead, I saved the draft and just when about what distracted me, and came back to this unfinished post.
Leaving posts behind means that you will need to come back to them. This is one of the actions that many people forget, leading to half-done projects, posts, and articles. When I know I want to commit to writing anything, I first look back on what is half done.
Setting aside 20 minutes may not seem like a real commitment that will stack up to a meaningful contribution, however, 3 instances leads to an hour. When we are working at our best, our work is higher quality and more meaningful. 60 minutes of quality work frequently out-does 4 hours of dragging and being full of anxiety, only to give myself negative self-talk.
4. Write when you want to write, and don't when you don't
Forcing writing is one of the best ways to end up hating it. That's why doing short amount of writing in the long run will be less stress than forcing long times of writing commitment. Instead of thinking about published for a date, I'll create when I want to - and if I do finish the project, I sit on it. Currently, there are future posts for the blog schedule to come out in the future, so that my work produces a regular stream of content even if I do not. Instead of being frustrated when I have motivation or energy but nothing to do, I use that time differently be easier on myself when I don't want to do anything.
5. For things like lectures, articles, and blog posts, I utilize my high energy and motivation times and "bank" it for later. Using this blog as an example, I wrote this post at three different times where I felt motivated and attentive to the task, and then I scheduled the post for later. Here's an example, and a little preview of some upcoming posts.
I hope these strategies help someone else be able to accomplish their writing goals with a little bit less stress <3