In the following paper we describe the influence of various factors on the reliability of pipeline inspection results. Special attention is paid to in-line inspection of pipelines. If inspection results are not only used for immediate repair programs but also for long-term risk assessment the importance of different input parameters has to be rated. In some cases inspection results yield important information would remain unheeded if no special attention would be directed to it. In the end we discuss the importance of properly archiving inspection data for long-term risk assessment. Available software solutions for properly working with in-line inspection data seem to lack in compatibility with data of different sources. A possible road towards standardization is shown.