Some exams can be forced by power, and some requires strategy. Sometimes, basic ninjas like Hinata, Kankuro, Naruto etc is much better to use, and/or fits your strategy to pass a certain ninja exam. If you are lazy, and dont want to throw a certain amount of time finding a strategy, then you might not beat it. Power is not everything.

PS: I hate those Zabusas and Kakashis in ninja exam. They can wipe your team in just one round.