Jesus' every utterance was truthful. He did not soft-pedal or flatter. His words had integrity, and people could count on what he said. Truth permeated all of his interactions. We want to be encouraging but we should encourage only with words of truth.
Flattery helps no one.
It gives the disciple inaccurate feedback and it undermines the credibility of the mentor. Some Christians make the opposite mistake, however, believing that telling the truth is a license to be harsh and critical. It is not. Telling the truth well means considering the needs of others. Religion is the best and most reliable means we have to reinforce the good.