Naruto Uzumaki: Everyone... everyone... has risked their lives to come after you.
Sasuke Uchiha: Well, how good for them.
Naruto Uzumaki: Believe it.
Kakashi: Uh, Naruto, your speech was cool and all, but if you lose any more blood, you're going to die.
Deidara: Art is... with a bang.
Rock Lee: A dropout will beat a genius through hard work.
Answer: That is just a style used by some animators. It is easier to keep the arms in one position than to draw them in motion. And it makes it look funnier.
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