Anchor Bias Is Why You Reveal Blind

We’ve all been in a planning meeting where the senior developer looks at a ticket and says, “This looks like a 3,” and suddenly, the entire team magically agrees.

This is called anchor bias. Human brains are wired to rely heavily on the first piece of information offered. If the most experienced person in the room drops a number before anyone else has a chance to think, the rest of the team will subconsciously adjust their own estimates to match it.

The Silent Cost of Going First

When anchor bias takes over, you lose the entire point of estimation: uncovering different perspectives.

Imagine a junior developer who actually sees a massive flaw in the database architecture for a specific ticket. In their head, it's a 13. But because the tech lead just called it a 3 out loud, that junior developer will likely stay quiet, assuming they just misunderstood something. They vote 3 to avoid looking foolish.

Two weeks later, the sprint blows up because of the exact database flaw the junior developer saw.

This is exactly why estimation poker requires a blind reveal. Everyone selects their card in private, and the numbers are only flipped when the whole team is ready. If the junior developer picks a 13 while the senior picks a 3, you just found a critical knowledge gap that needs to be discussed.

The fix: Stop estimating out loud. Use an online estimate poker tool that forces blind voting. It levels the playing field, removes the social pressure, and gets you accurate estimates instead of a room full of nodding heads.