No: there need not be even one orbit tending to zero. Partition the domain into the disjoint intervals
and, for the unique with , define
The left endpoint is strictly below , so . Moreover and , so remains in the same interval. For every iterate,
Every starting point belongs to some finite-index interval, so this proves the claim for all . The open left endpoints matter: an orbit approaches a boundary but never crosses it. This is discontinuous trapping of decreasing iterates, not a violation of the bounded monotone sequence theorem; each orbit does converge, just to a positive value where continuity fails.