* Lectures let you see how well your audience is getting it (assuming you're lecturing to an audience). So you can tell what's making sense and what's not.
* You can talk faster than you can write. In fact, in my experience, I can talk about as fast as I can think. I can't write as fast as I think. This makes me inclined to skip over some thoughts while I'm writing, simply to keep up.
Incidentally, I don't see why the first point ("There is no post-lecture work, such as rigorous editing or re-organization of ideas") is really an advantage of lectures. Certainly there are many lectures I've seen that could have used some reorganization. And, at any rate, any decent lecturer will do preparation beforehand to organize the presentation.
* Lectures let you see how well your audience is getting it (assuming you're lecturing to an audience). So you can tell what's making sense and what's not.
* You can talk faster than you can write. In fact, in my experience, I can talk about as fast as I can think. I can't write as fast as I think. This makes me inclined to skip over some thoughts while I'm writing, simply to keep up.
Incidentally, I don't see why the first point ("There is no post-lecture work, such as rigorous editing or re-organization of ideas") is really an advantage of lectures. Certainly there are many lectures I've seen that could have used some reorganization. And, at any rate, any decent lecturer will do preparation beforehand to organize the presentation.