When the mempool is congested, your transaction is basically like taking a number in line: first thrown into a pile of "unconfirmed," miners/validators pick the ones with higher tips first, and if you tip less, you keep getting left behind, sometimes even to the point where you forget you ever confirmed it. Others think that seeing large transfers on the chain or activity in exchange hot and cold wallets means "smart money is positioning"; in reality, it's often just someone moving positions, topping up margins, and at the same time making the network even more congested. To put it simply, when you're in a hurry, don't fight yourself—I'd rather send it later or increase the fee to a level where I can sleep peacefully. The crazier the market, the more I feel that being a step behind isn't really a big deal.