So, around the forums I see posts similar to:

"RC checks should take some thought, it's not just mindlessly doing them."

"You should genuinely question reality."

But... I'm not exactly understanding what that means. How long should that actually take? A couple seconds, maybe a minute? And whenever I do RCs in waking life, I already know I'm not dreaming because I remember everything up to that point and the RCs fail. Also, how can you accurately measure "awareness" in a dream?