Most people who work have some form of official objectives that they sign up to. These will be used to measure their performance, and there may be performance bonuses which are linked to these.
A well known model to help you to create better objectives is the SMART framework, which stands for Specific, Measurable, Achievable, Relevant and Time bound.
Objectives created under this framework are good because they remove ambiguity from the objective, while allowing a measurement framework to be developed for the objective.
Specific objectives will say exactly what you need to deliver in the appropriate level of detail.
Good objectives are measurable and allow allow a qualitative or quantitative performance measurement to be made.
Stretching yourself to achieve great things is wonderful, but make sure you the objective is bound by reality. Unrealistic objectives will make you fail.
Objectives need to deliver outcomes that mean something. Achievement of your objective should go some way toward delivering your companies (or your own) priorities.
Finally, a great objective will have a timeframe; when will you complete this task.