Trump not necessarily saying he wouldn’t accept the result of the election but leaving it open falls into play with his “election is rigged” comments. It leaves voters wondering if indeed the election is rigged. If Trump has such strong beliefs, with backing, then why would he simply say all is okay? The voters, by his answer, are left to ponder a rigged election and that focus goes right to the Clinton campaign as scoundrels.
Found this: "The American businessmen, as a class, have demonstrated the greatest productive genius and the most spectacular achievements ever recorded in the economic history of mankind." - Ayn Rand
America, Give Trump a Chance to fix our great nation.