WHY???

Can anyone tell me why on God's green earth? You've got a cup of coffee. You've drunk as much as you want. You take the cup to the kitchen counter. (Said counter is adjacent to the sink.) WHY would you not DUMP OUT that little bit that you did not want??? Why just set the cup on the counter and walk away? Did you intend to come back later and drink it? Tomorrow? Next weekend? If so, don't leave it by my sink. If not DUMP it OUT! (Teresa, this means you!)

P.S. I am VERY easy to get along with. :-)