I tend to disagree with people on the "numbers game" thing. The barriers to submitting a million resumes to a million jobs have never been lower, so people in charge of hiring are inundated with applications from people who's skillsets and stated interests make it clear that they have not even read the job posting. It makes it so that people who are fitting for the job are like a needle in a haystack. It also doesn't help that the people reviewing applications are not often the people who you'd be working with, and they don't necessarily know all the right things to be looking for; they just have a list of magic words that they are filtering for. You might have a synonym of the right word on your resume, and they'd never notice it.

These days, knowing someone is especially the key in my experience. It doesn't even have to be someone you know well enough that they'd give you an actual "recommendation". You are probably better off sending your resume to 10 people who already have the job you want than submitting 100 actual applications.

It's not the best resume in the giant stack who gets interviewed, it's someone's niece's college roommate's former coworker's step-cousin.