Strong Markov property and its meaning

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Given a sequence of random variables $(X_n)_n$ (fulfilling the Markov property) and a stopping time $\tau$ such that $P(\tau < \infty)=1$, we have that $P(X_{\tau+1}=x_1,X_{\tau+2}=x_2,...|X_{\tau}=x) = P(X_{1}=x_1,X_{2}=x_2,...|X_{0}=x)$. I don't understand where the stopping time comes into play. Why is it not equivalent to say that $\forall n \in \mathbb{N}: P(X_{n+1}=x_1,X_{n+2}=x_2,...|X_{n}=x) = P(X_{1}=x_1,X_{2}=x_2,...|X_{0}=x)$?