I’ve always disliked that phrase. So much of what I’ve achieved has been through working harder than the next guy. I’ve also been blessed with a mind that gives me the opportunity to work smarter.
Each can be an effective strateg in its own right. In soccer I can outwork and outlast equally, or more, skilled opponents. Given more time, I can increase my skill and have that as a tool to supplement my tenaciousness.
Work hard, and while you do so, think about how to improve efficiency.