Originally Clock 23 was supposed to demonstrate the sensitivity to initial configuration for which non-linear dynamics is famous. It accomplished this by releasing a particle pointing away from the second hand once a second: each subsequent minute would see the particle released at a particular second subject to a slightly different configuration of hands, and hence a difference configuration of forces.
In the end, the generated traces (which did show that, occasionally, small changes in the configuration of the system lead to large changes in the dynamics of the particles) were sort of boring. Adding a small repulsive force to the dynamic particles produced a more interesting set of generated images.
One nice thing about programming for the purposes of generative art, rather than for modeling, data analysis or application development, which have been at various times my day jobs, is that one is free to do things for purely aesthetic reasons.