This study empirically analyzed the mechanisms behind the few Fast-Track decision cases and the regression to standard acquisition procedures using Grounded Theory methodology, despite the implementation of the defense Fast-Track system. Open coding, axial coding, and selective coding were conducted based on in-depth interview data from 15 defense experts representing the Ministry of National Defense, Joint Chiefs of Staff, Army/Navy/Air Force, Defense Acquisition Program Administration, Agency for Defense Development, and Korea Research Institute for Defense Technology Planning and Advancement. The analysis revealed that ambiguity in Fast-Track designation criteria and the burden of audits/regulations act as causal conditions, while TRL verification uncertainty and conservative budget reflections act as contextual conditions, leading to the central phenomenon of “sluggish Fast-Track decisions and loss of institutional differentiation.” The core category derived from the selective coding analysis is “the generalization of Fast-Track caused by responsibility-averse risk response.” This refers to a defensive coping mechanism where working-level personnel and decisionmaking bodies surrender their discretionary power under Fast-Track and make a conservative retreat to the safest standard acquisition process due to the structural pressure of bearing full accountability for post-audits, allegations of favoritism, and technical failure risks. This phenomenon was verified to manifest through four main causal pathways: (1) audit/administrative burden type, (2) technical distrust/performance gap type, (3) system/budget estrangement type, and (4) responsibility-avoidance/procrastination type. To resolve these issues, the study proposes customized policy alternatives, including clarifying post-audit exemption conditions, completely omitting reporting procedures to National Assembly standing committees after requirement decisions, applying flexible evolutionary ROC, introducing simplified TRL fast-track verification, establishing dedicated reserve funds and budget tracks for Fast-Track, and building a top-down policy responsibility-sharing system.
