Including a job objective on your resume is optional. Here are two important reasons to include an objective: to state your career goals or to show that there is a match between your skills and employment goals and the position you are applying for.
As with the rest of the resume, your objective should be tailored to the employer. A good objective example is: Seeking a widget sales position with a top 10 widget manufacturer in which I can utilize my eight years of experience in widget and widget accessory sales.
This shows both knowledge of the company, and showcases your experience - briefly. The rest of the resume should revolve around this theme.