Several millenniums before Christ, in the Mexican Indian Civilizations along with the two count measure and the accented beat in music - came the rock step. Naturally, as a separate step, the rock step evolved into more .Now the "break" became defined as the first part of the rock step. And the dancers just naturally "broke" on the accented beat. In rock forward, the dancer steps forward with full weight transfer then transfers the weight to the back foot while keeping it in place
"An optimist believes we live in the best of all possible worlds.
A pessimist fears this is true."
In modern partner dancing, the lead breaks on the accented beat and the followers are just the greatest. When it became Americanized and accented on the first beat, then everyone in the US broke on the one beat. Sometimes the terms rock step and break step are used interchangeably, and there can be a stylistic difference but that is for fancy dancers. As social dancers we try to stay with the KISS method (keep it simple, stupid.)
"Por Un Amor" por Graciela Susana
Back a couple millenniums, with the Chassé, came the choice of dancing it to a two count as in samba or a three count as in Viennese Waltz. (More Later) The music and dance evolved into the 4,5,6 and even 7 counts, but the seven count measure became obsolete shortly after the arrival of the first illegal aliens to the Americas. At the height of the Mayan empire, they may have had as many as three thousand different dances. These were professionals.
"We may not be there yet, but we are closer today than we were yesterday."