Because they have limiting beliefs about themselves and the world. It creates a self-sabotaging cycle that can result in a life of regret. We all have the power to manifest our dreams, but in order to do, so we have to shift to a more positive way of thinking. Using the Law of Attraction to manifest your dreams is about actively holding yourself in the energetic space of infinite possibility.
It's curious that people who believe in a LOA are critical of those who don't and believe them to be close-minded. I have presented a lot of new data such as the erroneous science and the data showing that acting as though you had already accomplished your goals was detrimental to you doing so. Yet, LOA proponents do not look at this with an open mind and reconsider their belief system. In this way LOA is akin to a faith-based religion, except that religious beliefs can't be disproven.

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