I think our minds just gather more information than what we always consciously notice.

Sometimes I'll say some notion of mine outloud and I'm surprised that other people haven't noticed it. Like I think everyone notices as much as I do, but apparently they don't. Usually the notions have something to do with people.

For one example, I once noticed one of my friends has lost a lot of weight in the past because of stretch marks all over their body. From their old Facebook pictures it could be pretty much confirmed the stretch marks were due to losing weight. The theme of weight and weight loss etc. somehow popped up in a conversation between me and another friend (the friend who has lost lot of weight was our mutual friend) and I also mentioned this one, mutual friend. My conversation partner was very surprised, they hadn't noticed at all. And I thought it was like "common knowledge" or something.

Also, I once met a guy from Tinder. He was sure he didn't know who I was, even though we went to the same uni and same courses etc. We had even had prolonged eye-contact in one certain uni course (before we had ever matched in Tinder). I asked him if he was SURE he had never seen me around. He was definitely sure he had never met me before. And there wasn't really a reason to lie, he was a very straightforward, talkative guy otherwise.

I found it very weird. If I see some people repeatedly in the same premises, they're like stuck in my mind and I can't stop noticing them again and again (I'm sorry, I'm not a stalker, it just happens). It's usually like this; of course there can be some people that escape my field of perception and naturally I can't say anything about them because I haven't noticed them (?). But according to the conversations I've had with people, not everyone seem to notice as much things as I do (sounds boastful but everyone can make their own mind about whether or not it's a good quality).