The handbook talks about finishing the race, of not becoming discouraged. Challenging work usually takes time. Results may be slow in coming. Slow results are
an indication that the work is worthwhile and challenging.
Salvation of souls depends on success. We should refuse to accept defeat. No case is hopeless.
A steady application of Legion methods will over time, turn even the hardest of cases.
Is it worth the effort? We work for a year and only get one or two people back to the sacraments. Remember Jesus would have under gone his passion if only one person was saved.