Concepcion made the hard plays look easy. Ozzie made the easy plays look hard.
The reason it is called the Hall of Fame instead of the Hall of Skill is because perception is more important than reality. Ozzie was more famous, Davey was overshadowed by the Big Red Machine.
As this thread has proven, it is very difficult to differentiate the skills and production of the two players. They were extremely similar both offensively and defensively. Yet one of them was a sure-fire first ballot Hall of Famer and the other one will never be inducted.
It is just another example of why the Hall of Fame is not very meaningful. There are several players in the Hall of Fame that have absolutely no business there, while some of the best (and most famous) players the game has ever seen are not there.
I am always amused when the debate for/against players like Ozzie and Concepcion turns to their offensive "prowess". Believe me, Ozzie Smith's election to the Hall of Fame had absolutely nothing to do with his hitting ability.