Expectation of $v=\inf \{n\geq 2\,;\, X_n > X_1 \}$ when $(X_n)$ is i.i.d. uniform on (0,1)

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Let $W$ be the occurence meaning the following ordering : $X_1...X_k$ where $X_k$ is greatest.. $X_k$ is greatest, and next in order is $X_1$, and the order of the others is not important. Because of the independence of the occurrences and equal distributions of the variables , we have $**P\{v=k\}={1 \over k(k-1)}**; k=2...$ Therefore $Ev= \infty$

I highlighted what I don't understand , can anyone clarify this with a little more detail?