The early generation of scholars dedicated their lives, and had the capacity, background knowledge, and ability to extract laws from the Quran and sunnah yet there arise laymen among the muslims who think they can “just do it” (as nike says). It was a long process to come up with a science of fiqh, its not something individual muslims can do on their own. Among what they did, scholars travelled to learn hadith, they made sure it was authentic, they compiled them, then they deduced laws and set up a fiqh system after much revision and consultation. When it came to Abu-Hanifa over 50% of his rulings were rejected by his own students after they learnt new hadiths/knowledge. The science of fiqh was a longterm educated group effort. So would you trust the work of many dedicated and outstanding scholars (in which the early ones had links to the prophet & sahaba) or yourself or a random muslim who thinks their opinions are true based on their very limited scope of islamic knowledge. A big alhamdullilah for the scholars of islam who took on this massive task, as the prophet SAW said, its scholars who inherit knowledge from the prophet. This is NOT something individual muslims can do and this is why we are told to respect and learn from scholars. Otherwise islam would become like any other religion, where every person has different opinions on rulings and interpretation of the quran and sunnah. Where even one person would contradict his own self because he doesnt have a system of fiqh. The ummah would become completely divided.