Although Zeus, Poseidon, and Hades did their best to conceal and guard the Book of Eternity, there were still people who wished to free Cronos and use its power for evil. The Titans loyalists were immortals that wanted to release Cronos and bring back the glorious days of the Titans.
Finding the Book of Eternity and freeing Cronos from his captivity were the only means the Titans' supporters saw to achieving their aim. They were also aware that the book was secured and that the Olympians would do anything they could to conceal it.
Zeus, Poseidon, and Hades conceived of the EternalProject in order to secretly mobilize for a fight against Titans loyalists. These magical objects not only functioned as a way to keep track of the people who could be relied upon to safeguard the book, but also as a shield against the Titans' acolytes. The EternalProject also aided in keeping their identities as the book's guardians a secret.
Despite the Olympians' best efforts to keep the book out of hands, the Titans' supporters persisted in their quest to find it. Using every resource at their disposal, they persisted in their search for the book. Some of them were in positions of power in different parts of the world, and they manipulated the dreams of ordinary people in their quest to find the book.
The Titans' supporters would resort to violence or fraud if they thought it would help them win. Because of the danger they posed to the Olympians and the world, the heroes understood they had to do whatever it took to put an end to them.
There was a serious threat to the Olympians and the world from loyalists to the Titans. In their pursuit to free Cronos and read the Book of Eternity, they were prepared to resort to any measures necessary. The Olympians would do anything to stop them and keep the book safe.