Say what you mean, mean what you say

There was once a host who organize a party. Some of his guest did not show-up so he said “Why hasn’t the one that should come, haven’t arrive yet?” when the guest that has showed up for his party heard what he had said walk out of the party feeling insulted and that they should not have come to his party. To make matter worst the host seeing his gust leaving said without thinking “oh! Now the one that should have stayed have left!” the remaining gust left the party thinking that they should not have stayed.
From this story it is clear that it is important to think what your listener may feel from your comment. You may not meant what you said but people may interpret differently from what you mean.