If you've gone into stealth mode around enemies, you've probably noticed a little meter that pops up on screen. Sometimes it will say [Hidden] other times it might say [Caution]. The basics are easy to pick up on.
If it's green and says "Hidden" you're hidden from the view of your enemies. And if it says "Caution" there's a chance that you could be seen if you aren't careful. Here's something that you might not know.
If the brackets around the words are far apart, you're in a good position. If they're close together, your chances of being spotted are greater. So, for instance, [ Hidden ] is better than [Hidden].
If you're playing a class that relies on stealth or you occasionally like to infiltrate enemy locations without being seen, make sure you keep a close eye on this.