Request For Assistance: How and What Makes a Description Compelling?

I will apologize in advance if this post goes off into a mindless rambling. My thoughts are somewhat unsystematic in how I approach things.
This post may or may not devolve into a long tl;dr (Too long, didn't read) mumblings of a dense moron whose claim to fame is your typical, if somewhat unorthodox shipping of Applejack and Spitfire. (If only there was a wy to save drafts of blogs and guides on how to outline and that jazz. Oh well.)

Anyway, back on topic.

Seeing as I have no idea how to start conveying what specific concept I can narrow down exactly, I suppose I shall start with the detailing of the flaws in my own prose.

To me, my writing either comes off as too repetitive or stilted and without imagery. Descriptions based on sense seem to come off as brittle, without any sense of familiarity of the reader themselves. OF course, this will vary from person to person, yet I cannot help but wonder what kind of description will work. What is that specific "something that I cannot narrow down specifically but list in a general sense" problem that I have in my writing? I do know I have yet to find any form of pre planning outlining of a story to be up to my satisfaction. Save for some basic details, my planning phase seems to come off as muddled, incoherent, and without any form of structure. I also cannot tell what the reader will visualize based on my writing, something that is my thoughts constantly when I write. Words don't seem to have that "oomph" factor that makes that clear to the reader's mind. The passion and intensity of some of the better prose on this site gives the impression that the author knows from the heart of their soul which words fit so well in a puzzle that I cannot figure out.

I have done countless months of research on the Internet to prepare myself in writing a story. Yet all my efforts seem to meet with no avail, with the concepts presented in guides being intangible and without a form to grasp. Guides may present their concepts to a decent degree, but actually comprehending and solidifying them into a shape that can be grasped and deduced from examining it is another story. Perhaps it is some lack of perspective that has proven to by my weakness here, yet I still wander aimless without direction on where to start and go. What details have I missed? What have I not accounted for? Details get muddled and lost in a void of white noise. Dialogue and plot progression feels forced and without point sometimes, even if I had established some form of proper reasoning from my perspective as to why they are valid.

This ends my current line of thoughts for today, seeing as class is about to begin. I shall return to this blog and update it sometime later down the line when appropriate.