In some patients, the improvement of symptoms is not obvious after epilepsy surgery. The reasons for this are mainly the following three situations: (1) complex cases, where the epileptic lesion is difficult to locate clearly; or due to conditions (e.g., the patient’s economic situation), the coverage of intracranial electrode examination is incomplete and the information of the data obtained is not comprehensive. (2) Multifocal epilepsy, where the epileptic origin may be located in different parts of multiple brain regions. The epileptogenic foci can be compared to “volcanoes”, some of which are active and some are transient, and when the active foci are removed, other transient foci may activate and cause seizures. This case above is a multifocal epilepsy with two epileptogenic foci in the frontal and temporal lobes, respectively. (3) There are some epileptic disorders that are inherently dynamic in their development.