But what is wrong with using the word “but”?  There’s nothing really wrong with “but”, but isn’t it possible there’s a better way to communicate? 

So what I’m really saying is, “There’s something wrong – or at least problematic with that tiny three-letter word.  It separates the first statement from the statement that follows. And that is just fine as long as that is the intent.  If I’m attempting to create distance between one thought and another then “but” is my word.  “Our streets are littered with trash but it doesn’t have to be that way.”  There – in that sentence I want to discount the first statement as having less power than it may at first seem.  However in this sentence, “You finished most of the problems on your math paper but you didn’t do the last two” the word “but” leaves the recipient with a sense that the first part of that statement was just a lead-in for the real message, that of incompetence.  Is that really what was intended?  If not, perhaps “and” (another three-letter word and a beautiful connector) is more helpful as in “… and you just have two more to do.  You’re almost done!”  Would you be more motivated if the person making the comment to you acknowledged your efforts so far, or discounted them as “not enough”?