Often when you send a job ad out, you get millions of emails - many people blindly applying to any job. It's maddening and becomes a real chore working through the CVs and cover letters. But it's unnecessarily difficult if you spend some time figuring out who you're trying to target, and how you might be able to give them an advantage/opportunity to stand out.
I've recommended adding silly little tasks/questions to job ads to pre-qualify candidates, and it's worked very well in the past. Instead of receiving 100 emails (estimates to prove a point), I might get 10 - but almost all 10 would be perfect candidates. It's really just understanding marketing.
You can read the full article on Medium here.