Ah. So roughly like this: If you can convince people in advance that you can do it, and you find it satisfying for people to think you can do it, you've achieved half of your goals already and therefore have less cause to actually finish the project.

In this model, the effect will be less pronounced when the anouncer doesn't believe that the anouncees really see them as being bound to complete the project. This could be achieved in two ways; the anouncer hears them doubt, or imagines that they doubt. Give open doubt to naive dreamers to help them to avoid this trap.