I tried once, monitoring the same transaction simultaneously through the browser, wallet prompts, my node's RPC, and an indexing site,

and the times displayed across all four platforms could be off by several minutes...
Basically, what you see as "on-chain" is often "on-chain data provided by a certain service."
Slow node synchronization, RPC queuing, the indexer not having scanned it yet—just like watching a fork battle live, there's always someone a half-step ahead of you.

Recently, everyone is obsessively watching staking unlocks, token unlock calendars, afraid that as soon as the time hits, there will be a dump,
but if you're relying on data that's already delayed or missed scans, your anxiety might just be a delayed delivery...
Anyway, now I tend to wait two more minutes after seeing "on-chain activity" before deciding whether to get itchy.
That's all for now.