I suspect that, like many, you were unconsciously putting some effort into the mantra. I prefer to use the term "hearing" the mantra in you r mind, rather than thinking it or saying it in your mind.A small difference in attitude can lead to a huge difference in efficacy.
@@peter-russell Instead of saying the mantra or thinking it in my mind , i photo it in my mind as a FONT (like in ms word the difference fonts) and when i get distracted i hear the mantra lightly (whispering) in my head and go back to a different font but i do see the mantra word and even its sound changing into something totally different. Still trying to make perfect with the effortless part. I havent been taught TM. But watched hundreds of videos and articles about it gather the really good ones and do it. As best as i can … I finally saved enough money to go to a trained TM and be taught the proper way which ill be doing within the next 2 weeks. IM SO excited! BTW : after I do the TM or even mindfulness meditation i feel drowsy not energetic , but i do feel my thoughts and mind not wondering and my negative thoughts disappearing . Super excited to get trained by a TM certificate teacher to bring it to the next level.