What is the use of pin caution?

A pin cushion is a small stuffed fabric pad used for storing sewing needles and fabric pins as to keep them together, tidy, and sharp, and the cushion also prevents accidental needle pricks when placed onto it after each usage thereby avoiding loss of the needle in clothing, furniture or body injuries.

Pin cushions come in a variety of shapes and sizes. Many include small felt pouches that hold thimbles and other miscellaneous accessories required for sewing that don't fit directly onto the pin head such as threaders.