Some cards come with spend caps, meaning you might be able to only earn a certain number of points per statement period. For example, you may only be able to earn up to 7,500 points per statement period. After you have reached this cap, you'll either continue to earn points at a reduced earn rate or will be unable to earn points until the next statement period.
Check your credit card's terms and conditions for details of points caps and consider whether it could impact your points earning potential. For example, if you have a card that earns 1 point per $1 up to 7,500 points per month, you would only be affected by the cap if you spend over $7,500 each month.