First, the biggest reason: human factors. Because the data is not measured accurately, if the data is not processed accurately in the measurement process, the final result will not match other existing measurement results on the one hand, which will affect the next experiment; On the other hand, the measurement error of the measured value eventually leads to the wrong experimental results, which leads to the failure of the experiment.

Second, other possible reasons: experimental environment. This reason is an external objective factor that affects the experimental data. It is suggested to debug the equipment carefully to ensure that the equipment is in the best condition when used.