These days I've been looking into MEV/ordering issues, basically on-chain "cutting in line" to be the first to execute a trade. Many people think it's just arbitrage bots fighting each other, but the most painful part is for regular traders swapping currencies and market makers: you initiate a swap, the price gets pushed up first and then slammed back down, and slippage gets eaten; LPs think they're earning fees, but sometimes a chunk of their range gets "siphoned off," and the losses aren't visible on the surface.

Not to mention recently some regions increasing taxes, tightening and loosening compliance policies, and changing deposit and withdrawal expectations, leading to more aggressive on-chain orders. The more urgent the orders, the easier they are to get sandwiched. Anyway, I now prefer to earn a bit less, split trades into smaller parts, set tighter slippage, and choose more "fair" routing when possible—it's about long-term gains, not treating yield as a get-out-of-jail-free card.