Recently, I saw someone say "On-chain data is the most authentic," and I can only say... authenticity is quite real, but what you're seeing might already be "outdated."

Nodes sync slowly, RPCs are rate-limited, indexers queue up for rebuilds, and by the time you look at that transaction in the browser, it's actually several steps behind, especially in places like DEX routing, where a delay of a few seconds can change the fee structure.

When I was a beginner, I thought: as long as it's on-chain, it’s real-time and everyone sees the same.
Now I understand: on-chain is consensus, but what’s displayed to you is a service. The RPC provider, the indexer, the caching strategy—there are big differences.

By the way, these days there's a heated debate about privacy coins/mixing compliance. I’m more concerned about "what exactly is your RPC filtering or missing," to be honest. When data access points tighten, what everyone sees on-chain might become even more different.
Anyway, when I do small experiments, I try to cross-check multiple sources to avoid being misled by the "delayed truth."