Your First Draft Sucks. If you are constantly trying to plan everything ahead of time for your story, writing will feel like a chore, and you are more than likely to not finish it. But if you take the advice of just start writing without any concrete plans, then you are more likely to finish it. But it is going to suck. It's going to suck a lot. But it's there, you have it written out. That is when you edit it, fix the grammar, remove some things. Turn it into your second draft.
Well, your second draft is also going to suck. But it will suck less. Writing is about editing and editing. What you spend most of your time on, is editing your drafts. And what I think most writers, and perfectionists like me, need to know is that no matter how many times you edit a draft, it will never be perfect. Not saying it will be bad; no, it will be good, but as writers we tend to keep trying to reach that 100% to make it the best thing on the planet. And we lose sight of our original love for the story. Get your drafts to a point that you are happy with.
So, write your bad first draft, turn it into your decent second draft. And before you edit it too much, find peace in that 99.99%.