you do not "need" to wash after claying, usually you would polish anyways which would remove any residues left behind.............wash, clay, polish, seal (wax) (add a beer (or 2 or 3 or.....) in there somewhere and your complete):beer :lmfao
I gave my car a quick wash after I finished with claying it. I couldn't get all of the residue out of the small cracks and openings by just wiping as I went. Took about 5 minutes.