Conservative Bias
We're slow to update our beliefs when new evidence arrives, clinging to what we already think.
What it means
Conservative bias (sometimes called belief conservatism) is our tendency to insufficiently revise our beliefs in the face of new evidence. When we receive information that should shift our understanding, we do update - but not enough. We cling to our existing view more than the evidence warrants, adjusting at the margins rather than rethinking from scratch.
This isn't the same as ignoring evidence entirely (though it can look that way from outside). It's subtler than that. You do take the new information on board - you just give it less weight than it deserves, because your existing belief has a kind of psychological gravity. The longer you've held a belief, and the more you've built on it, the harder it is to revise substantially.
Conservative bias helps explain why paradigm shifts are so slow - in science, in business, in personal life. The evidence for a new reality can accumulate for years before anyone acts on it, because everyone is making small, conservative adjustments to their existing worldview rather than accepting that the whole picture has changed.
In the real world
A company has always sold products through physical retail. Online sales data has been growing steadily for years, and industry reports suggest a permanent shift. The leadership team acknowledges the trend in every board meeting - but their strategy remains fundamentally retail-focused, with online treated as a side project. They've updated their beliefs, technically. Just not nearly enough.
The thought to hold onto
Noticing new evidence isn't the same as properly accounting for it. The question isn't "have I seen this?" but "have I let it change my mind as much as it should?"