When the network is congested, submitting your transaction is basically waiting in line in the mempool... but this line doesn't follow first-come, first-served rules; it depends on whether your tip is enough. You might think "I just click confirm and it's done," but in reality, your transaction could be stuck there, repeatedly bumped by others, or even pushed out when it expires; what's more awkward is when you leave it hanging, and others have already pushed the mempool fee higher, causing your transaction to either suffer from slippage or fail altogether, wasting your fee, which can easily frustrate you.

I usually pay close attention to this part when looking at new projects: congestion = the best cover for "exit timing," especially for contracts that can change tax rates, blacklists, or suspend trading permissions. By the time you wait in line forever, they can toggle permissions, and you won't even know how you lost money.

Recently, there's been an upgrade/maintenance on a major chain, and everyone is guessing whether projects will migrate. I think there's no need to jump to conclusions about migration yet; first, observe how the mempool and block space change before and after the upgrade—whether it's congested, who is racing to get ahead—these are more real than slogans. Anyway, I give myself a "patch": in a big market, don't rush to be first; I’d rather wait for two more confirmations than send my transaction when others are rushing to front-run.