I will try my best here to don't make this theory exhausting of reading, and explain that zoans will oftenly find their way with users of similar will/personality.According to what was told by Jupiter Warcury in Wano, all of the zoans have their own will, specially mythological ones. Once awakened, they can lead to three paths, the 1st: the zoan's will will overwrite the will of its users and transform them into a mindless animal, as it was shown with the guards of Impel Down. Whatever personality they had, it was possibly overwritten by the will of their zoans, or the user already had a matching neutral personality with the personality of the zoans and their mindless, feral state, moving by instinct is just a proof of this. (Possibly these guards of Impel Down were some numbers that Kaidou didn't purchase and were used as guniea pigs?Who knows, they are fodder anyway LMAO)2nd: Once awakened, the zoan will, of course, give extra powers to the user, and a misterious white cloud-like smoke will appear around their neck.Known characters to have awakened zoans with the smoke cloud-like around their necks are: Monkey D. Luffy, Yamato, and, with the chapter 1140,Saint Kirigham Limoshif. Luffy has a matching benevolent personality that matches with the spirit in the Hito Hito: Model Nika: seek for freedom for himself and his friends/allies. Same goes for Yamato. Yamato wants to protect Wano, and his/her Inu Inu: Ookuchi no Makami is known for being the spirit protector of Wano. Saint Kirigham Limoshif: while being technically considered as a villain, at least for now , he has the mythological power of the Kirin, a creature known for respecting all life forms, known as a paragon of virtue, goodness, justice and wisdom, depending on the version of the myth, so it is possible to speculate that he either is a traitor (the theory of having a traitor amongst the world government isn't new), will be a traitor, or will have his redemption by the end of the series. Not to mention that it is not clear exactly how they obtained their powers: possibly given by Imu, or obtained like other devil fruit users usually do? Who knows? Worthy remembering that it was already proven that Imu Nerona is not oniscient, as Saint Saturn against the orders of Imu was studying Emeth for over 200 hundred years, rather than destroying it and got away for a long time, before paying his price, and other characters like Mjosgard, Homing and Corazon also were acting on their own and Imu didn't do anything against them, possibly not knowing of their actions.Now, for the awakened zoan users with the black lightning-like cloud around their necks.Rob Lucci: a bloodthirsty world government assassin that that has the Neko Neko: Leopard. They have matching personalities, as Leopard are known for being ruthless and bloodthirsty predatorsKaku: Though he has a more soft and calm personality, he has the Ushi Ushi no mi: model giraffe. Giraffes are calm mammal and herbivorous, but can become quite dangerous and step on smaller preys, which may justificate (or maybe not) the black lightning-like smoke around Kaku's neck. Who knows what might happens to his smoke if Kaku returns redeemed and becomes an ally of the Mugiwaras or even the Revolutionary Army?* The Gorosei/Figarlang Shamrock: No need to elaborate here, do i?*Others: Kaidou, the user of Uo Uo No Mi: Model Seiyaryuu. While being technically considered as the strongest creature alive, Kaidou didn't have his zoan awakened and i will try to elaborate my theory here of why it happened. It is because Kaidou's strenght had some great use for the Uo Uo zoan spirit, but they didn't have matching personalities. In fact, they are opposing.The Uo Uo is derivated from the chinese legend of the carp that has to swim a waterfall and once it reches the top, as a reward, the fish becomes a blue chinese dragon, however, once Kaidou ate the fruit, he instantly gained access to his dragon form without needing to overcome any difficulty to awaken. You know who did that? Monkey D. Luffy in his battle against the former captain of the beast pirates, and, in a poethical context, all of the people of Wano. The Uo Uo spirit was making use of Kaidou's strenght to have Luffy awaken his nika form by climbing a "waterfall", (or better yet, ascending to heaven, to return later awakened), through here, i presume that even if the zoan has not a matching personality with the user, the zoan can fulfill his will using the user's strenght, or possibly Oda simply didn't want to give Kaidou the awakening for he already being too strong the way he was.What are your thoughts over this all that i wrote? Make some sense, or just a bunch of random ggiberish? Yeah, i copied this theory from myself, Mr. Katakuri at the Worstgen site, just in case of someone finding the thread over there.