Goals must be SMART:
S - Specific. It should not be ambiguous or vague. Not just the wishful thinking. Needs to be Specific enough to motivate you
M - Measurable. If we cannot measure it, we cannot accomplish it. Measurement is a way of monitoring our progress.
A - Achievable. Achievable means that it should be out of reach enough to be challenging but it should not be out of sight, otherwise it becomes disheartening.
R - Realistic. Unrealistic goals can never be achieved. It just makes you depressed.
T - Time-bound. There should be a starting date and a finishing date.