In ancient times, there were no sources of artificial light, and it was difficult for people to judge the length of their nails accurately in the dark. Cutting and disposing of nails was challenging, and pieces of cut nails were considered unhygienic as they scattered around the house. Additionally, people had fewer amenities, and they had to cut their nails with sharp objects, often resulting in injuries in low light. Seeking medical help at night was also challenging, so people avoided cutting their nails in the evening.