Why do common household items (shampoo, toothpaste, medicine, etc.) have expiration dates and what happens once the expiration date passes?

Question

Why do common household items (shampoo, toothpaste, medicine, etc.) have expiration dates and what happens once the expiration date passes?

In: Other

Answer 1

Expiration dates do not describe the point of a product being bad but rather a point until the product will uphold the standard of quality. Shampoo and toothpaste might single out some of it’s chemicals and thus not be as effective.
A good example of this is instant coffee which still produces the same tasting coffee but the powder itself clumps together and you have to scrape through it to use it.