Score high in ALL the introverted functions!

I've been slowly learning about the cognitive functions and taking a few quizzes along the way. While the results vary quite a bit, what's consistent about them is that for every function, I score higher in the introverted attitude than the extraverted attitude.

http://cognitivequiz.com/quiz.html: Ni - Ti - Te - Si - Fi - Ne - Fe - Se. (Ni and Ti were both very high and very close to each other.)



http://similarminds.com/classic_jung.html: Ti - Ni - Fi - Si - Te - Ne - Fe - Se. (Interesting pattern there. This one identified me as most likely INTP.)

http://www.keys2cognition.com/explore.htm: Si - Ti - Te - Ni - Fi - Fe - Ne - Se. (This one identified me as most likely ISTJ.)

I understand that there are not many conclusions we can reasonably draw from this information. The different quizzes describe the functions in different ways, and so on. But the more I think about it, the more certain it seems that I really do use the introverted versions of each function more than the extraverted ones. It's more of a close call with the judging functions than with the perceiving functions, possibly because while I consider my inner world to be the standard, I don't want to miss some important bit of information from the outside world, and I answer questions accordingly (resulting in Te, Fe catching up to Ti, Fi).

Has anyone else noticed a pattern like this? What about extraverts - do you find all the extraverted functions to be stronger? Or is this "pattern" attributable to the inherent error in taking quizzes like these (it's not likely to actually exist)?