What I never understood

If I say that I can understand the person’s mindset, why they drew the conclusion they had based on the information they found; that doesn’t mean I condone anything they say or do that’s wrong. It also doesn’t mean that I don’t understand what they’re saying or doing. If I say that I can see why they’d think a certain way, that doesn’t mean that I agree with them.
Yet saying that I can see where they’re coming from tends to cause more issues in my conversations with others than anything else. What is the disconnect here? This is the one thing I can’t ever understand. I don’t get why they don’t get it. 😵‍💫

So I get quiet. Every time. With everyone except one other person who I’ve expressed this issue with.