<prompt> Human: For clarity, take the American Express Delta Sky Miles card. If, after signing up, you spend 3,000 in the first 3 months you are awarded 30,000 miles on Delta. This is a one-time offer. My question is: what stops a person from signing up for the card, acquiring the 30k miles from the intro offer, then canceling the card? What would the penalties likely be?  <response>: Generally, there is no penalty for doing this. What you are describing is the whole idea behind rchurning. Check out that subreddit for more information. 