Jim Thompson understood something about the serial killer before the psychology caught up to it, which is that they are detached to it and they do want to get caught.
They prospect of seeing oneself in the mirror clean-shaven is too close to a Vincent Price film... a prospect not to be contemplated, no matter the compensation.
I must confess that, at that time, I had absolutely no knowledge of the slowness of the relaxation processes in the ground state, processes which take place in collisions with the wall or with the molecules of a foreign gas.