Is it really important to follow one madhab? Why can't we follow them all?

So Madhabs are there to provide a principled approach to how we understand Islam, how we derive rulings, how we make new rulings. Now if you're, let's say, somebody who doesn't have a Madhab, it's not a problem at all. You don't need to worry. Allah says in the Qur'an: 'Ask somebody of knowledge, whoever that person may be, if you do not know.' So if you don't know, all Allah asks us to do is ask somebody who is qualified, who has studied, who can give you an opinion based on Islamically what you should do. That's all you need to do. The Madhabs there are to provide us and to help us in order to make rulings. Because, as an example, you open Sahih Bukhari, you find one hadith the Prophet said, 'Do not visit graveyards.' Clear hadith. You turn the page, you find another hadith the Prophet says, 'Go and visit graveyards. Make sure you visit graveyards.' So how do you understand these two hadiths? This is why the Madhabs are there, they provide principles and we understand it by saying one hadith was at an earlier time in Islam, the second hadith came later and abrogated it, and so on.