Assessment is the tendency to be thoughtful and deliberate about everything they plan to do. It is a tendency to evaluate and compare things extensively, be self critical and critical of others and be judgmental and perfectionistic.
The locomotion and assessment scales were published in the following paper: Kruglanski, A. W., Thompson, E. P., Higgins, E. T., Atash, M. N., Pierro, A., Shah, J. Y., & Spiegel, S. (2000). To "do the right thing" or to "just do it": Locomotion and assessment as distinct self-regulatory imperatives. Journal of Personality and Social Psychology, 79(5), 793–815. https://doi.org/10.1037/0022-35220.127.116.113