Lately, I keep seeing people complain about "unfair ordering" and "validators making a killing again," which is pretty normal. The on-chain system is basically whoever is better at front-running gets to go first. Do retail investors need to study block builders and bundling to a paper-level detail? I don't think it's really necessary. Just knowing that "your transaction might not be included in the block in the order you submitted it" is enough.

My personal baseline is: if I see slippage suddenly spike, the transaction price is unreasonable, or even with a limit order it gets swept, don’t immediately blame your shaky hands. Think about whether you got front-run or sniped. There are only a few tricks: don’t try to trade aggressively when liquidity is thin, don’t set too loose slippage, and when necessary, use protected routing/private channels (to avoid broadcasting to the whole network as a target), or just wait for the next liquidity wave before acting. Tired but still watching the order book… Anyway, arbitrageurs just have this fate.