I'm trying to understand the logic around the Mempool. What I understand is a miner will pick transactions based on an incentive given by the sender, i.e. a fee, so that the higher fee, the faster transaction will get confirmed.
But, What if the transaction get picked by a single miner regardless of fee and that miner is very unlucky miner that somehow it never win the block hashing lottery. Is that possible?
My question is:
Is only a single transaction picked by a single miner and the miner hashes the transaction with other transaction, then guessing the nonce, if it wins, then it includes in the block, else return to the Mempool?
Or,
Is only a single transaction picked by multiple miners and all those miners hash the transaction with other transactions, the guessing the nonce and the miner who wins the lottery included it in the block?