Every turn is a new cube decision. Always. Never forget. The biggest error you can make is to fail to double at the appropriate time.
Kent Goulding, 1991

A player who is savy with the cube will have an advantage over an opponent who moves the checkers slightly better but makes inferior cube decisions. Thus, it is vital to understand cube decisions in order to be a winning backgammon player.
Kit Woolsey, 2002

The doubling cube holds the key to being a winner or a loser. Good checker play will never compensate for serious errors of judgement on doubling. A good part of the skill is accepting or refusing doubles lies in being able to recognize which positions are gammon prone and which are not. In any position where you are under attack and have no anchor in your opponents board, you risk being closed out and gammoned. Many seeminly inferior positions can be taken when you have an anchor.
Paul Magriel,

And someone said I dont know who: you win games with checkers, you win matches with the cube.