Just a wonder

In sermons and in bible classes teachers and preachers and people of all kinds often ponder the wonder of what Jesus bend over and wrote in the sand when the Pharisees and the Teachers of the Law brought the woman "caught in the very act" of adultery to Jesus. They speculate that He could have been writing this... or maybe it was that that He was writing.... or perhaps........?

Here's my wonder:

Why are people often more curious about what Jesus wrote in the sand that He didn't tell us about, than what He actually did? Why do we seem more interested in what He failed to tell to say, than what He inspired in His Word to be scripted and passed on for all of these years that He's preserved because He wanted us to hear?