Reasons why the school system is failing us can be for multiple reasons. For starters, people say we don't learn about important things needed to succeed after life in the secondary schools as we should. Do we know how to file taxes? Sew? Know what a deductible is in insurances?
Another example I'd think is the way we are integrating technology into schools. I do think that the school system is nice that they are implementing something such COMMON in our lives, but starting off with technology so early on can only lead to circumstances later on.
These are quite examples and many reasonings can be used to answer this question.
Machiavelli uses reasoning and an example as evidence in an argumentative structure to support his claim that a prince must destroy a city that is accustomed to freedom if he wants to hold it.