First of all, we lose focus once in a while; not being able to stay on task and get the work done. The mind is puzzled, we lost the motivation to be able to pick up a pen and paper. Times get rough. Don't no where to begin. Days, weeks, and months just goes by.
You may have ideas or not but you wonder if your writing is good enough. You may sit and stare for a while. Thinking about having the right words. Getting stuck with the revisions. Another thing is that depression, sleepiness, or stress can play an role in it too. Having too much going on at once can cause anyone to lose focus and stop doing what they was doing. After all, we want to make sure our work is perfect for our readers.
That's where criticism comes into play. Our readers may say something about our work from time to time. But some won't. We are taught in life in general, to not let what people say get to us. Comments are going to come sooner or later. And we have to prepare ourselves for that.
Writer's block comes and goes. We all get it but once it is gone; we are back in our zone. Just writing nonstop and coming up with amazing ideas. Our minds are back on track. We have found our way again.
So, if you are looking for a way to prevent writer's block; try not to be hard on yourself. Give yourself a pat on the back. Reward yourself sometimes. Take a break but not too long. Maybe take a walk or do something else that you like to do that will help you relax. You could even try an writing exercise. Keeping ideas fresh on your brain.