A simple explanation is better than a thousand words, the ETH network works based on hierarchy. Who pays more will get funds faster and the rest will wait until the next mined block clearance happens. The cost of gas has increased a lot and $0.1 worth transactions in 2019 now cost more than $3. ETH2.0 should solve this infinite loop unless the market becomes volatile again.
actually we this while checking transaction on tx id. so high gas gwei will confirmed first by miner. i think it is not fair system for all user, system must use similarity in every transaction like other blockchain . many people complaining about this fee , even binance CEO also tweet about it if core developers didnt solved this problem in eth 2.0 it will be serious problem for eth.