Gas fee is the network fee you pay to carry out a transaction or smart contract action on a blockchain. Fees can climb when the network is congested. Smart contract interactions can cost more in fees than a simple transfer.
Why do fees change
It depends on network congestion, transaction complexity, and your priority setting.
Failed transaction
A transaction can fail if it doesn't meet the contract's rules, and you may still lose some of the gas fee.
Confirmation
The state where a transaction has been included in a block and confirmed by the network.
Practical habit
Before you hit confirm, double-check the address, network, amount, fee, and contract permissions.
You should see
Gas fees are the cost of using the blockchain network, and whether they're low or high depends on network conditions.