This research investigates the impact of attributes of line managers based on the Abilities, Motivation, and Opportunity (AMO) model in relation to effective HRM implementation. Conducted within an organization in the battery industry, the study measures HRM implementation through a performance appraisal system called Leapsome. A self-administered questionnaire, informed by previous literature on AMO and HRM implementation effectiveness factors derived from interviews with three HR department employees involved in developing Leapsome, was utilized. The questionnaire was distributed as per census data collection method, to 258 line managers via Google Forms, yielding 103 complete responses for analysis. Regression and correlation analyses were performed, focusing on three main dependent variables: effort, frequency of use, and alignment with deadlines. The results indicated positive relationships between all independent variables and the dependent variables, except for the relationship between ability and effort, which was not supported. Consequently, the hypotheses were accepted, except for the hypothesis stating that ability positively correlates with effort. The study concludes with managerial and theoretical implications and provides recommendations for future research.