Imam an-Nawawi رحمه الله said:
“Although the Sahaba and the elders of the first generation were superior to later day jurists {Fuqaha} and Mujtahid, yet they did not get an opportunity to compile and arrange their knowledge and its principles and branches. So, it is not proper to follow them blindly because none of their [the Sahaba] teachings can be pinpointed for sure. Compilation began later on by the Imams who had benefited from the Madhabs of the Sahaba and Tabi’in {Those Who Followed the Sahaba}.
They compiled their commands and explained their own basic principles and branches, like Imam Malik and Imam Abu Hanifah did.”
{Al-Majmu’ Sharh al-Muhadhdhab, Volume 1 pg. 91}