Everfrost and Rod of Ages are two AP items but do not enhance power as well as Luden’s Tempest or Rylai’s Crystal Scepter. They are also among the most criticized Mythic items by the League of Legends community.

A Reddit user named “VaccinalYeti” shared his experience and research through Challenger rank videos as well as watching streams on Twitch. These items are effective in certain situations.
Rod of Ages is often used in extended team fights and is specific to certain champions, such as Akali. With the reduction in tankiness forcing players to use Boots of Swiftness instead, Rod of Ages will provide a damage increase over the duration of the fight sufficient for Akali (up to 15%) and convert to true damage.

On the other hand, champions that seem suitable but cannot maximize their power with Rod of Ages include Swain, Sylas, Mordekaiser, Rumble, Ryze, and Vladimir. If players still want to build Rod for these champions, it is best placed as the second or third item in the build order. For example, Diana will be more effective with Rod of Ages instead of Nashor’s Tooth when facing opponents with two strong tanks.
As for Everfrost, this item is not favored by gamers despite its relatively quick slow effect. However, for champions with hard crowd control like Twisted Fate, Ahri, LeBlanc, Morgana, or Swain, Everfrost will be extremely effective.

Everfrost is an item that will be strong in the late game, so don’t worry if you have a relatively tough early phase. Especially, if you have all 5 Mythic items, Everfrost will help players gain 155 AP.
Although it still provides a decent amount of power late in the game, it is clear that for AP champions, Everfrost and Rod of Ages are not essential items. In fact, by the time players acquire these two items, their opponents may have already reached their power threshold. Therefore, Riot needs to make specific adjustments so that Everfrost and Rod of Ages can be more effective earlier, such as allowing Everfrost to grant players 155 AP without requiring the number of Mythic items.