Zabuza was Right
"So let me get this straight," said Shikamaru. "You can use your clones to do a year's worth of training in a single day; but you don't want to, because… Why, exactly?"
"It feels like I'm cheating," whined Naruto.
"You are a complete fucking moron," said Shikamaru, stalking off.
"Say what you will about the Uchiha," he thought, "But at least he doesn't treat being a hired killer like it's some sort of game."
A.N.
Cheating? What do you think this is, the Olympics?
This is the kind of argument that appeals to the NaruHina mentality: the successful are despised for their 'unfair advantages' (e.g., looks, popularity, skill, wit, etc.) by the unsuccessful people wishing -and only wishing, rather than putting in the effort to develop their own potential- to 'magically' acquire those same qualities themselves.
Of course, Kishi also opened up a whole fucked-up can of worms with the god-like powers of the Sharingan and the Kage Bunshin. The characters' abilities were suddenly off the charts, and their enemies/rivals had to be exponentially more powerful in turn. Now, instead of ninja using chakra-based techniques to render effects similar to Industrial-era weapons (and limited in their use by factors such as strength, experience and affinity), we basically had Clash of the Titans.