It's not the form that's the issue. It's the required depth of that thought, when you are actually doing the work yourself you need to go all the way in your thinking otherwise it simply won't work. When you're vibe coding, your thinking only goes as far as you see necessary so the AI has enough context to give something useful in return. It's like comparing the thought process of an analyst and of the engineer that implements the spec, any engineer knows that difference.