Basing the tier list off of tournament results is simply backwards logic. Tournament results SHOULD reflect the metagame or the tier list, not the other way around.
Think of it as a class.
Just because you pass a class, it doesn't mean you know the material. However, if you know the material, you SHOULD pass the class.
Likewise, just because Jiggs had top placings, it doesn't mean she is at the top. However, if Jiggs was top tier, she SHOULD have top placings.
The reason why I emphasize "should" is because in real life, there are other factors changing the outcome. Like character representation for example.
Similarly, in school, you could know all of the material and have all the potential, but still fail the class because of other factors such as: test anxiety, laziness, having a ***** for a teacher, etc.
Jiggs just happens to be that not-so-smart kid who worked really hard and got a higher grade than the know-it-all-Asian-kid Fox who slacked off all year like a douchebag.
****, somebody tell me they get it.