Good timing means remaining consistent with the movement/count . This means dancing on the same beat during each measure of the song.
So what is the most important rule? FIRST LEARN THE RULES, THEN BREAK THEM. This is the best tip, to improve and be better at dancing salsa especially the timing. This means I DO have to know WHY I am not following the rules. In fact, I can stand ABSOLUTELY STILL during an entire eight-count beat. But I must do it purposefully, to punctuate the music, to tell the story the way my body wants it told.
The importance of timing increases when you dance with a partner. Why? it serves as a challenge for the lead-follow relationship, you can observe here unknown movements, meet a call-and-response environment, you can learn new steps to experience the unity of two people, you can have someone to tell your story to (silently, with your body), and of course make friends.
It is better to dance an entire song doing the basic step with correct timing, than spend 3.27 minutes whirling and spinning without any regard to the beat of the music. Timing is the FOUNDATION of dance. Once you have that solid, THEN you can begin to turn, spin, and dip.

