When I was in my late teens /early 20s, I would tend to miss them more unless they were really obvious. With time and practice, I noticed them a lot more, but still found ambiguity in them i.e. "Okaayyyy...I know this is not good, and this person doesn't really mean what they say, but they could either mean they want me to do A, or do B, or leave them alone..." - and with my processing speed for these scenarios, it's a toss-up, sometimes I get it right, sometimes partially right, sometimes totally wrong.
As long as it's something you have to process to some extent in the conscious realm, and not entirely subconscious, it will be subject to error.