There might be too much emphasis on the power that positive thought has on your life.
It it good to think positive thoughts? I don't think too many people would disagree. If it does nothing else, it certainly can give you good vibes.
But with the ideas coming out of the New Thought movement of the early 20th century, it has been claimed that thought can manifest your desires.
This is very pervasive, and a little sinister as well since the proof cannot be obtained of this. Moreover, the ideas and techniques fully shield themselves from any actual result successful or otherwise.
To clarify, one of the central tenets of the Law of Attraction is that thoughts are things, and whatever you put your mind to, you will attract without knowing it.
The "without knowing" part is the cloaking device since it removes yourself from your own manifesting scenario and leaves it up to the Universe to take care of.
If you didn't get what you desired, your thoughts were just not vibrating on the right frequency.
There is simply no accountability. There is only fuzzy pseudo-logic wrapped up with pseudo-science.
Repeat affirmations to get your thoughts vibrating on the right frequency
...and leave it right there.