We study the evolution of an elastic string into the pinned state at driving forces slightly below the depinning threshold force $F_c$. We quantify the temporal evolution of the string by an {it activity function} $A(t)$ representing the fraction of active nodes at time $t$ and find three distinct dynamic regimes. There is an initial stage of fast decay of the activity; in the second, intermediate, regime, an exponential decay of activity is observed; and, eventually, the fast collapse of the string towards its final pinned state results in an decay in the activity with $Am sim (t_p-t)^{psi}$, where $t_p$ is the pinning time in the finite system involved.
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