People often say, "I saw on the chain that address XX just bought/sold," and I want to ask: which "on-chain" are you actually seeing? Any delay in the node, RPC, or indexer layer can make your view lag by a few seconds to minutes. To put it simply, blocks first appear on a few nodes, then are transferred to you via RPC, and then organized by the indexer into the pages you're familiar with; lag, reorganization, rate limiting—all can turn an event that has already happened into something you just saw. When a major public chain is about to upgrade and everyone guesses whether the project will migrate, I actually care more about whether, during that period, RPC glitches or indexer backfill delays cause the on-chain data chart to jump erratically... Now I get used to cross-referencing multiple sources, at least two RPCs plus a self-built light node for verification—it's a bit of OCD, but it’s peace of mind.