Recent on-chain congestion, I sent a small transaction that looks like it's queuing in the mempool to buy milk tea... To put it simply, you first toss your small note saying "I want to transfer/convert coins" into the queue, and miners/packagers prioritize those who pay higher tips. If you're stingy with the tip, you're only left waiting, and while waiting, the price might slide away before it gets on-chain. Actually, the most annoying part is thinking you've already moved out, but you're still at the tail end of the queue. Anyway, at this point, seeing large transfers or hot and cold wallets of exchanges move is often interpreted as "smart money." I also get tempted, but I've learned my lesson: set limit prices and slippage first, so a single candle doesn't eat me up like a snack.