A paging message is sent to all cells of a LAC, trying to reach a specific mobile phone (= SIM card).
If the mobile is not in the cell, there is a paging failure. Since the mobile is only in one cell, you have a failure in all the other cells.
If this is how the paging success is counted, then it is normal to have a low success rate for paging… If it is not counted like that, then I don’t know (there is no such indicator in Alcatel systems)