Looking at this Arbitrum transaction, it's a harvestReward call on a staking/rewards contract.

The 1 USDC argument is the minimum amount out parameter — a slippage protection mechanism. It's saying "only execute this harvest if I receive at least 1 USDC worth of rewards."

This is NOT setting a maximum. It's the opposite: a minimum threshold to prevent the transaction from completing if:

• Rewards are too small to be worth the gas
• Price slippage occurs during any swap involved in the harvest
• MEV bots sandwich the transaction

Think of it as: "Don't bother harvesting unless I'm getting at least 1 USDC back." If actual rewards are 50 USDC, you get 50. If they're 0.5 USDC, the transaction reverts.

Common pattern in DeFi yield strategies — protects against wasting gas on dust amounts or getting rekt by slippage during reward claim/conversion.