Despite decades of methodological advancement in spatial design, a persistent gap remains between design intentions and actual spatial utilization. This paper terms this recurring expectation of predictable outcomes the “myth of prediction,” which refers to the belief that design interventions can reliably determine how spaces will be used and experienced. Through historical analysis of spatial experience research, this paper examines how three major lineages (phenomenological, empirical-analytical, and neuro-architectural approaches) have attempted to address this challenge. While each offers valuable insights, all remain vulnerable to instrumentalization when institutional pressures demand predictive certainty over adaptive nuance. This paper argues that the intent-utilization gap is not a problem to be solved but a structural feature of complex adaptive systems. Complexity science provides analytical tools for understanding why predictive approaches systematically fail and suggests reframing architectural practice from pursuing predictive control toward cultivating adaptive capacity. The contribution is conceptual: offering the “myth of prediction” as a diagnostic tool and complexity science as an analytical framework for navigating persistent challenges in spatial design.