Voice is a skill to be developed, like any other writing skill. Give yourself permission to stretch it and challenge it and expand it and enhance it.
Looking like a finished work isn't what a first draft is for. It's a tool to help you tell the story.
With regard to writing, it sounds like you have a process that isn't working for you. That's not something wrong with you or with your process; it's a mismatch, like someone putting on a shoe that's much too large for them.
You have to pace yourself, like an athlete with an injury doing slow small exercises before returning to marathon running.
Drafting is engineering and construction. Revision is art and design.
If you still want to write even after you let go of any feelings of being obligated to write, take some time to think about why. Are there ways to access those motivations and keep them in the front of your mind so you can gain some satisfaction and joy from them?