Have you ever wondered why it is so difficult for some people to accept change?

“It should be borne in mind that there is nothing more difficult to handle, more doubtful of success, and more dangerous to carry through, than initiating change.”

The innovator make enemies of all those who prospered under the old order, and only lukewarm support is forthcoming from those who would prosper under the new. Their support is lukewarm partly from fear of their adversaries, who have the existing laws on their side, and partly because men are generally incredulous, never really trusting new things unless they have tested them by experience. In consequence, whenever those who oppose the changes can do so, they attack vigorously, and the defense made by the others is only lukewarm. So both the innovator and his friends come to grief.

(Niccolo Machiavelli, The Prince, 1513)