I don't have a problem with writing. When I have an idea in mind I find it easy to construct sentences to express my thoughts. What I struggle with is what comes before large writing projects and the prospects of publishing major projects I care about.
Allow me to elaborate:
The stage I struggle with before the actual writing is the outlining stage, or creating a structure for what I'm writing. For short posts, there's not much structure and I don't need to complicate the outline (for this article I know I want to write about two of my writing struggles and I will write about each in turn). But for bigger projects (long blog posts or books) I tend to over-think and over-complicate how the piece is meant to be structured. This overthinking can often stop me in my tracks: I'm unable to write anything because I'm not too comfortable with the structure of the piece.
I find it useful to have a model that simplifies the topic I'm writing about. This can be an acronym that sums up the main ideas, a number of factors to write about (10 productivity factors, 7 life areas, etc).
I used to struggle with publishing because I would be afraid what others might think of the piece and, if it's a paid product, whether it will make the sales I want to make.
I learned to treat sales as a separate experiment for me to conduct and refine. For now I should just focus on publishing and tweak my sales process as I go along.
What are YOUR major writing hurdles?
I'd love to find out. :)