Kojiki-Den [古事記傅] volume 1, Explanation by Itwse (004)
Or, if it after Kojiki editing was started, Teiki has enough contents, so Kojiki wasn’t needed, but the introduction of Kojiki says “although the times change, the thing still hasn’t been done.”, therefore, when thinking about this introduction, this record and that record seem to have the different meanings from each other.
The reason why both of those are different meanings from each other, should be recognized that the editing for Syoki wanted to make it looks like Chinese records, and the editing for Kojiki wanted to bequeath the facts of ancient times.
We can find editor’s motive in the introduction.
Then in the period when there was the capital in Heijou-kyou, Kenmu-Tennou had accepted the purpose of that motive, and had ordered Oono-Asomi to edit the record based on the old matters memorized by famous Hi-No-Da-No-Ale.
And the record that was edited in Wado 7 (714) must be one given a embellishment.
Furthermore, in the period Yoro (717-724), it ordered Toneri-No-Miko to edit Syoki.
The reason why, thus, those was edited in succession, must be thought that two embellished records was not able to make Mikado to be satisfied.
Therefore, these seem that quickly became unattened around that time, so these are not handed down in the current era, and even the names are become unknown.
However, Syoki was recognized as to be the superiority over the preceding two, then it is decided as the standard record of history, and the similar editing had not been gone after the decision.
Nevertheless, Kojiki seems that it has continued to exist since the Syoki released. That reason must be that the record is not a kind of previous two adorned with embellished, and it is recorded to the true of ancient times.