When is something "pretentious"?

[Alex K]

I'd say a work of art is pretentious when if presents itself as original and profound when it is really derivative and mundane.

Okay: "Sometimes a person's greatest weakness is his greatest strength."
Pretentious: "In my years of experience, I have observed something that few people notice and that is that the weakness of a great man is the strength that makes him great."

Or, as I always say,
One of my key objectives as an analyste de la société is to conceptualize the best-in-class framework based on the exploitation of the homo infirmitatem suam robore principle as an excellence-enabling asset.