What is the difference between product Shelf life and 7 year durability?

What is the difference between product Shelf life and 7 year durability unprinted?

Example: 6100XLP has a shelf life of 2 years and outdoor durability of 7 years unprinted.
  • Shelf life is similar to the milk expiration date stamped on the milk carton when the milk is fresh and has good quality. After the expiration date, the milk can sour and become unsuitable for consumption. For vinyl that are passed it's shelf life, it may have printing, adhesion, tight release or other performance related issues. It's best for customers to practice First In First Out (FIFO) and avoid this problem. Most common complaint of expired rolls are print quality or ink adhesion issues due to plasticizer migration.
  • Outdoor Durability address how 6100XLP will perform after installation and out in the world. 7 year vertical outdoor durability means that if the customer use a product that is within it's shelf life, the film will stick to the surface and not fall off or crack.