You can reverse the fishing line after you found the terminal segment has defect like fur.
PE line has been pull long during its manufacturing process and thus its molecules are aligned in the same direction (i.e. along the line) and thus mechanical damaged surface causing defects like fur. And damage would reduce the strength of the line and thus it is broken more easily. You can reverse the fishing line or cut the defect segment after you found the terminal segment has defect like fur.