I’ve had a number of conversations people as to the virtue of sketching v.s. wire framing. One reason for me is that it simply allows for many fast iterations, with less need to perfect, allowing my imagination to spark ideas. If I got straight to high fidelity wire frames I find it’s easy to get stuck in a rut.
I just stumbled upon this article on the subject on the UX Movement blog. A very interesting read and one that is inline with my thinking. Read full article here.