Caída comes from the Spanish verb caer meaning to 'fall' or 'drop'.
The 'caída' in Bulerías is the drop in tone at the end of a sung line, signifying a resolve in the letra.
As a dancer we want to be able to resolve at the SAME TIME as the singer with our movements.
The caída is important for us as dancers because it's our opportunity to interact with the singer in the moment and perform a remate, llamada, or other movement, that finishes (resolves) at the same time as the singer. With the caída. Olé!!