Why is it sufficient to check at one point on the orbit to determine the hyperbolicity?

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In this Wikipedia entry on hyperbolic sets of dynamical systems, on the examples section, it was asserted that "more generally, a periodic orbit of $f$ with period $n$ is hyperbolic if and only if $Df^n$ at any point of the orbit has no eigenvalue with absolute value 1, and it is enough to check this condition at a single point of the orbit." I am confused of why it is sufficient to only check at one point.