Well, thousands of people may have tried to answer that question. And each may have their own take on this subject.
But none it seems would be better placed than someone who not only has seen him work from close quarters, but also has an understanding of the field of investments good enough to make sense of what he sees.
If that is so, who better than Charlie Munger to answer that question. Munger is the Vice Chairman of Buffett's company Berkshire Hathaway since 1978. The two first met over 55 years ago, and have since been making investments and business decisions side by side.
A few years back, in a talk, Munger set out to explain the ingredients that made Buffett who he is. One of the biggest factors in Buffett's success as per him was the fact that Buffett is one of the best learning machines on the planet.
He went on to say that "The turtles who outrun the hares are learning machines. If you stop learning in this world, the world rushes right by you."
In fact, Buffett was still at it even after he reached retirement age. He was still learning effectively and building skills, even at that age.
Says Munger "Having watched the whole process with Warren, I can report that if he had stopped with what he knew at earlier points, the record would be a pale shadow of what it is."
How many investors do you think approach the field with such an attitude? Very few, we reckon.
Considering the sheer number of different industries and fields a business can belong to, we as investors need to constantly travel across a range of different subjects depending on which business we may dealing with at any given time.
No wonder than that having a 'learning mindset' or a 'growth mindset' could matter more than anything else.
So as we go through each day hoping to be better investors as we go along, let us ask ourselves - 'What new have we learnt today?'