Ritsuko was growing nervous and time was growing short. Gendo had insisted that she develop a new weapon to assist in the defeat of the angels. The last angel had shook Nerv mentally. Nobody had suspected that one angel could become two. The cross synchronization of pilots had worked to defeat it, but what if it hadn't worked?
That's why Gendo had insisted Ritsuko either develop herself or attain a new weapon that would insure they lasted long enough for the Human Completion Project to be completed.