As a rule, I avoid critiquing first drafts. I’ll comment on content and ideas, but nothing more. Why?
1. It’s not the best you can make it. Edit your work once or twice over and make it the best you can within your ability. Then bring in readers for feedback.
2. You’ll receive feedback you already know needs work. Comments I leave you’ll look at and go, “Well, duh! It’s a first draft, I was going to fix that in the next round!” Which leads into my next point.
3. It’s a waste of my time. It’s takes work and effort to read and critique, especially to polish a first draft. It’s a waste of my time for you to rely on me to make your work readable when it’s not even the best you can make it.
4. It’s a waste of your time. You won’t learn anything from my feedback, and so you won’t grow as a writer. It also takes time and energy to filter through someone’s feedback, and with a first draft I’m essentially a middle man telling you what you already know.
5. You’ll likely get caught in editing purgatory before you even finish your draft. Your work should be finished and free from this temptation. Editing a chapter back isn’t a big deal, but if you’ve edited your first chapter 70 times and the latest chapter maybe once, that’s a problem.
6. Scenes I edit might not even make it to the next draft. You don’t know what is solid in your draft until you go over it at least once and make it the best you can. If you leave scenes or elements you plan to cut, it’s not fair to expect a reader to give feedback on something you know won’t make it to the next draft.
TL;DR: Don’t be lazy. Edit your first draft to the best of your abilities before seeking feedback beyond general content/advice.