It is not always the case. These deceptive forces start playing when sadhana is undertaken under some spiritual ambition or lure of power or the desire for experiences. That is why surrender to the Divine or the Guru is so important for safety on the path. Sadhana should be done for the sake of the Divine, to know the Divine or the Highest Truth, out of joy and love for the Divine, to serve the Divine and His Will in the world. Wherever it is done for personal ends or for gaining worldly goods or to be spiritually great, etc., then the asuric Maya is attracted and starts taking the sadhak in its net of deception by a play and display of visions and voices and forces and experiences that imitate the Truth.
Affectionately,
Alok Da
