Your Resume Has One Job (You Can't Eat Your Car Keys)
/Your resume has one job: to get you an interview. This is why you don't need an objective on your resume. Your objective is to get an interview.
You are not going to get a job because of your resume. An effective resume can help you get an interview. From there, you'll need to demonstrate that you have the skills for the job and that you are a cultural fit in their organization. After that, you might get a second interview, or you might even get a job offer. But that rests more on how you perform in the interview.
To take a step back, the goal of your cover letter is to get your resume read; the goal of your resume is to get you an interview; the goal of the interview is to get you a job offer; the goal of the job offer is to get you the job you want!
Expecting your resume to get you a job is like eating your car keys when you're hungry. Your keys are just a tool that can help you get to the next step. Your car keys can help you drive to Dante's Pizza but that's as far as your keys can help.
If you're not getting many interviews based on how many resumes you're sending out, you likely need to work on your cover letter and resume. If you're satisfied with the number of interviews you're getting but not getting any offers, you need to work on your interview.