My understanding of leather is it should always be treated to extend its life. Otherwise, leather will dry and crack prematurely, especially if it gets wet on occasion. Whenever I inquire on the best leather treatment product, Nikwax is the hands-down favorite as it does the best job of "waterproofing", yet allows the leather to breath. Many products clog the pores in leather, and this is likely more harmful than no treatment at all. Be forewarned, leather is not waterproofed with any of these leather-treatment products, only more water resistant.