Different people have different mental styles. With me, I think it's really important to hear what people actually say - before you try to interpret why, and read between the lines, and follow implications. It's so common it's maybe even the normal thing to listen for WHY a person says a thing, and often then ignore WHAT they actually said... or else address it in an unfair, underhanded, too sure, or half-baked way. We assume the motives are the main thing, and we assume we know what those are.
It seems to me that telling someone WHY they said a true thing (or a likely/plausible/understandable thing), and focusing on that, is an express lane to trouble. It's just going to lead to bad conversations.
Now, you can address why they said the thing *as well*. But I think it really behooves everyone to address WHAT's actually said at face value. If we aren't doing that, we aren't having a proper conversation. It's always going to feel unfair if people aren't actually responding to each other directly. It's talking past each other.
Ultimately, you never know exactly why a person says a thing. Let them illuminate you on that. Don't try to dictate to them why they said it. That's going to come across as conversationally gross. You might be right, but the truth is you cannot be sure, so they are the main authority, and you are there to suggest motives inside themselves they might not have noticed or admitted out loud. But I think by far the best way to do so is in the context of listening to them carefully and treating them like real people. You don't get far with people by trying to stick a pin through them or superglue them to the worst interpretation. Even if the worst interpretation is correct, there were probably other motives and factors, so you'd still likely be (over)simplifying. Until you understand it how they do, you don't completely understand it - where "it" is what they're saying and why.
It's much less important to me why a person SAYS something than why they BELIEVE it. That is, I want to know their evidence and logic and experience. Just the fact a person thinks something is pretty meaningless to me. Who cares? Everyone thinks stuff. Everyone who's ever been wrong thought stuff - and it was wrong. Thinking a thing is not important, in a sense. But WHY you THINK that? Here's where you can make a real difference.
I'm much more interested in THAT why than in the why that gets a person to speak up in the first place. People are free to speak. They don't need to justify speaking in the first place, and you don't need to know exactly why they're speaking. In a sense it isn't really your business. By all means be interested. Even ask. Why not? But if you can't listen to someone until you know the why of their speaking up, or if your interpretation of the why of their speaking up makes you unable to focus on their actual, expressed words and sense - then I think you aren't really listening. You're half-listening and then imposing. And that's all too human. It's very normal. I just happen to think it's a mistake, because I've seen what it regularly leads to, and how much better things are when you use a better method. My why here is personal experience. But on some level isn't it always?