Compare against your alternative
The fair comparison is not against zero. It is against the best no-fee card you would use instead.
If a fee card earns 4% on groceries and your no-fee card earns 2%, the fee card adds 2% on grocery spend.
Multiply that difference by your real spend, and stop at any cap.
Count credits honestly
Statement credits are worth what you would have spent anyway. A credit for a service you would not buy is worth little.
Monthly credits that expire unused are worth less than their face value.
Lounge access and insurance benefits have value only if you use them.
Review each year
Your spending changes. Review the card when the fee posts.
Before closing, ask the issuer to move you to a no-fee card in the same family. This keeps the account open.
Some issuers offer a retention bonus when you call to cancel.
