Why is there a fan inside the computer case even if the case does not feel hot?

The fan inside a computer case helps maintain optimal airflow, preventing heat buildup from components like the CPU and GPU, which can generate significant heat even if the exterior of the case feels cool. Additionally, the fan aids in dissipating heat from areas where temperature sensors may not be located, ensuring that all components operate within safe temperature ranges. Continuous airflow also helps reduce dust accumulation, which can hinder performance over time. Thus, the fan is crucial for overall system stability and longevity, regardless of the case's external temperature.