It's a common misunderstanding about "mining" that when a miner processes(mines) a block it actually "verifies" transactions (TX) in it...Mining a Block has NOTHING to do with verifying transactions in the block. In fact, miners can only include one transaction (i.e. "coinbase", where miners receive their block rewards) & start solving "a difficult puzzle" (recomputing 2^256 of trials to arrive at specific "hash" function).
Verifying transactions are done by nodes, (computers containing Bitcoin blockchain, could be miners) checking 20 criteria to validate a TX and place it into their Mempool (something like RAM, a short-term storage for 0-confirmed transactions before they get picked up by the miners).
Bitcoin had a "first seen rule" fundamental, by which miners could choose to which block build upon. However, instead of developing on this concept, in 2015 a new "solution" introduced into protocol called Replace by Fee (RBF) (i.e. Bribing) . Users now can pay higher fees to miners so that their TXs get quickly picked up by them. The problem is that you won't pay a higher fee to pay for a coffee!
I'm not a developer but is this the best we could invent to deal with transaction fees/speed? Or this "solution" part of a bigger scheme to introduce Lightning Network & prevent blocksize increase?
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