Why length of string should be between 30 cm and 100 cm?

The length of a string between 30 cm and 100 cm is often recommended for practical reasons, such as ensuring sufficient reach while maintaining manageability. A string shorter than 30 cm may limit functionality, while one longer than 100 cm can become cumbersome, difficult to handle, or prone to tangling. This range strikes a balance between usability and convenience for various applications, whether in crafts, sports, or other activities.