An "authorized" state means that we've successfully collected the payment from the payer, but the transaction is in review by our Risk Management team.
Until the payment is in a "captured" state, funds are not credited to a merchant’s account. Since a refund would remove funds from the merchant’s account and give them to the payer, if the transaction then fails due to a risk decision the funds from the transaction also disappear, which would leave the merchant with a negative balance.
As an alternative to a refund, you can make a /checkout/cancel call while the payment is still in an authorized state. This will negate the transaction, and collected funds will be returned to the payer without any effect on the merchant’s account.