In the sphere of industrial applications, especially within the manufacturing sector, having a comprehensive understanding of a machine's status is crucial. While many companies boast advanced machinery, the neglect of monitoring machine conditions gives rise to numerous problems, such as reduced productivity and a high rejection rate. These issues translate into significant costs and environmental impact, highlighting the vital need for diligent machine status assessment. The purpose of this study is to determine the factors that cause a decrease in the effectiveness of equipment. This project also can determine the machine errors to investigate their correlation with idle time, minor stoppages, breakdown losses, and the fishbone analysis. Data collection was carried out based on 15 machines from March to May, which is obtained by expert interviews. The Overall Equipment Effectiveness (OEE) of 15 machines from March to May was calculated and assessment of the six big losses is conducted. The results show that mostly the machines produce products according to predetermined specifications based on OEE values. The idling and minor stoppages loss factor is the factor with the largest value was the main contributor to six big losses. The findings will provide industries comprehensive information on properly assessing productivity problems Consequently, these findings can offer valuable insights into appropriate methods for incorporating productivity analysis into the manufacturing process.