question #2 Sahih Muslim 363d, Book 3, Hadith 130 : How can the process of tanning be beneficial in making use of animal skins?

The Messenger of Allah (ﷺ) happened to pass by a goat thrown (away) which had been in fact given to the freed slave-girl of Maimuna as charity. Upon this the Messenger of Allah (way peace he upon him) said: Why did they not get its skin? They had better tan it and make use of it.