Why was "afflict you" (yamssas-ka) used with harm and "return you" (yarud-ka) with good in the noble verse?

Mentioning "touch" (mass) and "will" (iradah) is part of the Quran's varied expressions and eloquence. "Touch" (mass) is used with goodness in Surah Al-An'am: "And if He touches you with good, then He is over all things competent" (6:17). And "will" (iradah) is used when mentioning evil and harm in Surah Ar-Ra'd: "And when Allah wills evil for a people, there is no repelling it" (13:11). In Surah Az-Zumar, "will" (iradah) is used with both harm and mercy: "If Allah intends for me any harm, will they remove His harm? Or if He intends for me any mercy, will they withhold His mercy? Say, 'Sufficient for me is Allah; upon Him rely the reliant'" (39:38).