Few things are more frustrating within a team than confusion over goals and expectations. Not only do goals need to be clearly defined, but they must be communicated effectively.
If there is a misunderstanding between a leader setting goals and the team member executing them, both parties will hit a wall. No matter how hard someone works, if that effort is misguided it is both a waste of time and a poor reflection on the manager.
Sit down and make your objectives plain. Hash them out, and don’t leave the room until everyone is clear on what is expected. Better to carefully plan at the outset than face frustration later in the process.