<p>Regardless of extensive efforts in maintenance modeling for both periodically and non-periodically inspected reparable competing risk systems, critical aspects such as aging and the increasing failure rate over time are often overlooked. Dormant failures, which are non-self-announcing and remain undetected until a triggering event occurs, require specialized detection and mitigation strategies to ensure system reliability and prevent unexpected breakdowns. Present study demonstrates a novel approach to availability modeling for competing risk systems with dormant failures under sequential inspection. To accurately predict the severe damage potential of non-self-announcing failures, we implement a hybrid hazard rate model incorporating key elements such as the age reduction factor and hazard rate increment factor at each scheduled sequential inspection. This integration enhances maintenance strategies by enabling accurate assessment of component health and age, thereby improving failure prediction. Data collected on component age and health informs and refines maintenance actions. Preventive maintenance is conducted at each scheduled inspection to address potential issues proactively, while corrective maintenance is executed upon system failure. Using the hybrid hazard rate model at each scheduled inspection, we derive expressions for hazard rate, reliability, availability (both instantaneous and steady state), and cost analysis. Sensitivity analysis is performed to evaluate the impact of various initial inspection intervals on instantaneous availability. Furthermore, combined assessments of maintenance cost and steady state availability across different inspection intervals reveal the simultaneous effects of inspection frequency on both metrics. To validate the credibility of the finding at last a case study of an electric vehicle system is taken.</p>