Why do some of those who believe in a god refuse to consider the possibility they could be wrong?

Established theories have been tested again and again and again in attempts to prove that they are wrong. Each time, they have failed to be proven wrong. Let’s face it, if a theory is true, it will never be shown to be wrong, will it? At some point we run out of possible tests that could show a theory to be wrong. What possible evidence could there be that would show DNA does not exist in a double helix? What possible evidence could there be to show that the earth is not round? So, should we “consider the possibility” that these 2 theories “could be wrong”? Why?

Flat earth is a falsified theory. It has already been shown to be wrong.

A flat earther is in denial. There is massive evidence that the earth is NOT flat, but the flat earther refuses to acknowledge that. A scientist who does not “consider the possibility that an established theory could be wrong” does so because all the evidence 1) says the theory is correct and 2) there is no conceivable evidence that could show it to be wrong. All the conceivable tests have been done.

What movies and TV shows portray realistic beauty standards?

The claim that a scientist should always consider the possibility that an established theory could be wrong is brought up by people, who for reasons outside of science, do not like a particular theory and emotionally want it to be wrong. Maybe the reason is economic. Or the consequences of the theory are inconvenient. Or there is a religious reason.