Every anime fan dreams of seeing their favorite ongoing series come to a cathartic conclusion. Even if it takes decades for seasonal shows to finish their run, or even longer if the source material is incomplete, an outstanding anime finale is always worth the wait. However, not every series even receives a proper conclusion, either shut down after the first season or wrapped up hastily while the manga is still serializing.
Source:https://www.cbr.com/canceled-anime-best-beginnings/