Humans were born with limitations. That's something Roy has experienced firsthand. His basic stats couldn't go beyond 50 without external assistance because he has hit his limit. Only after awakening would he break a limiter and be able to grow stronger physically. But awakening stones and platforms were monopolized by the Royal Family.
Only by tackling the ceremony's trials and completing them to the very last one can one gain the chance to awaken.
But if you're able to break a limiter before awakening, then when you awaken, your second limiter will also shatter!
GhostWalker planned to shatter two of his limiters in the first stage so that his third limiter would shatter when he reawakens.
And… that would've been possible if not for Roy's interference. Because of Roy, the sole reason GhostWalker had joined this mission remained unfulfilled. Thus, he intended to finish him in a cruel manner. Punching the shit out of him sounded good.