KP is a good evaluator of talent. He has picked up some very good deals in the draft, where the pool is mixed with good and bad players.
In the trade market, the best players are not available. So, you have to value what is left and see if it works.
I'm guessing KP didn't see the type of talent he was looking for (for the price) and passed. He is likely going to get only one good shot at a major veteran--might as well make it a good one.
No trade today doesn't mean KP can't pull it off, just that he didn't see anyone worth the price.