Previous posters were right.
In Mark, it is clear that most people were simply “amazed and in awe” of the wondrous things he did. This is great, but they failed to see the true reality of Jesus Christ. They also saw the works, not the person.
In relating a story, don’t you think people would be like “This man, I forget his name, he was rockin’! He healed this man and it was so cool!”
People would flock to see him like some sort of attraction. It would be bad and Jesus’ mission would be brought to a screeching halt by the masses (which is pretty evident at times).
For a more theological interpretation, we can probably read out of the text that what Jesus is stressing is that we need to be converted ourselves. In the language of St. Francis, “preach the Gospel always, and if necessary, use words.” The idea being, we need to be examples, not mere relators of the Gospel.
Proclaiming the Gospel, in the sense i’m sure Jesus was stressing, would be unnecessary if people truly understood Him and followed him. But instead, people went off and proclaimed what he had done. As a result, when the teachings got hard, many people turned back, “Okay,” they say. “Show’s over. It was fun for awhile but I got work to do.”