How can Hafs ibn Sulayman be considered trustworthy in the Qur'an despite being untrustworthy in Hadith?

Hafs ibn Sulayman al-Asadi was a proficient and favored Imam in recitation (qira'at), even though the people of Hadith deemed him weak in Hadith. This does not diminish his standing in recitation, for his weakness in one art does not affect his mastery in another.