Why does inflation cause a countries currency to be worthless?

Question

Why does inflation cause a countries currency to be worthless?

In: Economics

Answer 1

A gallon of gas was $3 today, and is $6 today. So a $20 bill in your pocket will now buy only half the gas you could buy yesterday. So your money is worth less (than yesterday).

If this goes on long enough, gallon of gas gets to $300, and your $20 is worthless.