No matter how knowledgeable you are your eyes will fool you. We think Iverson looks amazing when he misses a double-clutch layup among the trees and think Ostertag looks like an idiot when he makes a layup. How can we fairly assess those players with our eyes? We can't.
It's the same thing Billy Beane went through. He couldn't produce, but no matter how many times he failed he always got another chance because he looked the part.
It's the same reason Sam Bowie got drafted over Charles Barkley. Barkley was two times the player (and had crushed him head to head in college), but he wasn't 7', and our eyes like to see 7'. Same reason Lin bounced around before getting a chance. We're not used to seeing a Chinese PG. It doesn't agree with what our eyes have associated with good basketball.
Economist Bastiat talked about the seen vs the unseen. The principle works similarly with regard to the obviously visible vs the less visible. In our minds we closely associate points with winning because of the visibility. What we don't see is that each rebound on average is worth 1 point. We don't make that connection, and fail to properly value them.
Revisiting the 1984 Draft: Was Bowie Really the Right Choice at the Time? | The Wages of Wins Journal