The dash helps to indicate that the two thoughts are intimately related, and it's less stodgy than a semicolon, which would have performed the same function (and who talks in semicolons?).

If I have any talent, it's in the artistic end of football. The variation of movement of 11 players and the orchestration of that facet of football is beautiful to me.

Your attitude will unlock the mystery of success you seek!

Nothing is more effective than sincere, accurate praise.

Your enthusiasm becomes their enthusiasm; your lukewarm presentation becomes their lukewarm interest in what you're offering.

Everybody's got an opinion. Leaders are paid to make a decision. The difference between offering an opinion and making a decision is the difference between working for the leader and being the leader.

Good talent with bad attitude equals bad talent.