This is not a beautiful drawing. It is an idea. Sketching should be all about ideas and not an effort to make something nice or beautiful. Okay, good sketches are beautiful but it's the idea that is beautiful, not the execution. Or rather, if the idea isn't there the sketch will not be so beautiful.
So this is a reminder to myself: Don't fuss with details, just try to get the big idea down on paper – as simple and straightforward as possible.
By the way, this thumbnail was done earlier today in Malmö. The tall thing is Turning Torso, the city's pride designed by Santiago Calatrava.