Why do we need to create lesson plans? Isn't the time it takes to come up with them and, more importantly, to cram them into the requisite forms, merely a distraction from important matters like recovering from teaching all day? I am an off-the-cuff sort of individual... can't you just take my word for it that I know the subject matter, and that I will think of an appropriate and engaging way to convey it to the students when the time comes? What's that? You can't? Well then, I suppose I'd better get back to work.
In all seriousness, lesson planning is vastly more interesting when I know I'm actually going to, you know, teach the lesson. More worthwhile somehow.