My rule is if I am not going to use it in the next 3 days, then I freeze what I am not going to use immediately. If you leave it in the fridge for a day or two before freezing, the quality is diminished before it is frozen. I like to keep the food the highest quality that I possibly can.
While it is certainly best to freeze as soon as the product in question is properly cooled to 41 or below, standard food code "allows" for up to seven days from the time it reaches 41. Why you would want to wait that long is another question.