Long-term manipulation is extremely difficult
In the short run, it's easy.
It's easy to fool someone or lie to them or give them what they think they want. It's easy to write a great block of copy, to sell on credit, to grab the attention of the mob.
Not so easy: to build mutually profitable long-term relationships that lead to satisfaction, trust and work worth doing.
Lincoln was right about fooling people, but along the way we often forget that while trickery is easy, the longer path of keeping your promises is far more satisfying and stable.