Suppose someone wants their car washed and vaccumed, and the next day its going to rain, maybe even the next 2 days it's going to rain. Do you still wash it? Maybe the customer doesn't know its going to rain, do you tell them? If its going to rain the next day, I'll tell the customer. Why bother washing it when its going to rain the next. If you do it, its money in your pocket, but you maybe faced with having to do a "raincheck" wash. Which is bothersome to tell the customer, you don't have it, and you jipped them? sorta?