... is having a clear way to explain to your employer how you can truly help him.
CVs often tell who you have been until now and how that can help predict your future performance, but they don't tell much that can't actually be covered by shady context. Sure, it takes merit to have the highest grades, but what about the process? Are you one of those who incessantly memorized the program, or did you take time to comprehend the actual meaning of the words? Did you study all by yourself or do you always need someone to organize your things? If you have work experience, what made you quit? And what made you join them in the first place? And what does that tell your employer about who you really are?
These are questions who are not asked because the sincerity of the answer is never fully verifiable. Instead, if you explain your worth in terms of adding value to that specific context (instead of how you added value by writing 14 full pages in an hour and a half or how you "actively participated" in a project), you'll have delivered a promise which you may keep or you may not. Hence, it gets easier to check if you actually deliver what you sell or if you're just a real good salesman.
Nailing that job is not about having a well-written, keyword-rich CV. It's about showing the ability to solve problems and save time. "Luck" also plays its role but more in the complex alignment of different elements which provide the right context for your pitch. An important part, but one you really can't control, can you?