The so-called "qualification certification" assessment system, at its inception, actually carried a greater meaning of "protection" over "honor."
The system jointly drafted by the Magical Affairs Institute and the Research Institute was simply to prevent magical girls, who were not very powerful at the time, from blindly combating Remnant Beasts beyond their capabilities.
Without reaching the White Card, don't blindly confront the Pupa Stage; without obtaining the word plate, don't blindly challenge the Metamorphosis Stage that exceeds Half-Molt. Tying strength with "qualification" rather than just judging by the Kaihua stage is a system to prevent the precious preparatory combat power from unnecessary wastage.