Why and how perception engineering sometimes fails

Perception engineering when it is not backed by conviction tends to fail in the long run. For example, the " Garibi Hatao" slogan of Indira Gandhi promised to remove poverty but even after four decades,it is yet to be a reality in India. Hitler's promise to turn Germany and Germans under the Third Reich rulers and masterrace of the world turned out to be a disaster though it brought short run successes. President Obama was voted to power on a promise of Change and " Yes, we can" but it is not yet certain the degree of change he has been able to usher in.