An Offer One Can't Refuse Meaning

(idiomatic) A threatening offer by one party for which the results of failing to accept are so unattractive that the other party is almost compelled to accept.

Example: 2006 Feb. 5, Michael D. Lemonick, "Are We Losing Our Edge?," Time:
  But in 2001 the government of Singapore made him an offer he couldn't refuse: the directorship of the brand new Genome Institute along with a $25 million starting budget.
1991 Sept. 22, Edward Rothstein, "Film: Hard Up for a Plot? Get With the Program," New York Times (retrieved 29 July 2012):
  The Mafia godfather Rocco . . . makes Jack an offer he can't refuse: marry Carol or else.