Conventional wisdom tells us that we have a higher chance of reaching our goals if we tell others about them. And it makes sense. The more publicly we announce goals, the more pressured we are into reaching that goal because of the fear of failure and judgement.
However, according to entrepreneur Derek Sivers, this school of thought is wrong. In his TED Talk, he explains why (using scientific studies) telling others your goals is a bad idea.
When you tell someone your goal, you already feel partially satisfied. This is what psychologists call a social reality. The mind is tricking you into thinking what needs to be done is in fact already been done.
Kurt Lewin, Wera Mahler, and Peter Gollwitzer (book here) are prominent psychologists that have written prominently about this phenomenom.
In Peter Gollwitzer's 2009 tests, 163 people across four separate tests wrote down their personal goal. Roughly half of the participants were allowed to announce their goals to the room while the other half were told to keep the goals to themselves. All 163 were then given 45 minutes to work towards their goal but were told they could stop at any time. Those who didn't tell anyone their goals worked the entire 45 minutes. When asked afterward, they said they had a long way to go still until they reach their goal. Those who told people their goal worked an average of 33 minutes but felt more closer to achieving their goal than the first group.
If you want to tell others your goal, tell it in a way that does not bring gratification to talking about the goal.
Those were the main points of the video, but if you want to watch Derek Siver's TED Talk, here it is below. It's under 4 minutes so it's definitely worth it to check out.