Here is a 1997 interview with Jeff Bezos that I like where he talks about why he created Amazon - https://www.youtube.com/watch?v=rWRbTnE1PEM. He describes a purely logical explanation of seeing data about internet growth and identifying books as being a uniquely good product to sell on the internet.
Which is not to say he wasn't "willing to dedicate [himself] entirely to solving the problem", but I think it agrees with your take about finding market opportunities rather than following a passion.
Which is not to say he wasn't "willing to dedicate [himself] entirely to solving the problem", but I think it agrees with your take about finding market opportunities rather than following a passion.