I knew what T was before I got it. My dad had it for 30+ years. But I still didn't pay attention because it is really hard to understand unless you have it. It's an invisible condition and you never think much it being something you will get. Other than my dad, I didn't know anyone else that had it in the past.
After I got T, I understood what it was all about. Then all of sudden, I was running into many people who had it: other relatives, friends and even some strangers. Even in my own department of 10 people at work-- 4 people had T, most for over 10 years. I got the same response most of the time- "yes I have it, hear it all the time" but it was no big deal so they ignored it. And they were fine. My dad after 30+ of loud military T is fine. People have it all around us and most just don't talk about it.
I think this was one of the factors that helped me get to where I am today.