Matins as one of the components of the Orthodox church service is held in the evening if combined with the Vespers into a special sequence, called the All-Night Vigil. Initially, according to the Church regulations, there were few such vigils in the year, but later, the vigils became more frequent.
Due to its long duration, the Vigil was an evening service which started in the evening and finished in the morning. Thus, Matins began around dawn.
Over time, however, the time of worship was gradually reduced, and if at first it lasted for about twelve hours, now its duration is two to four hours.
The main reason for this shortening of the divine service is that it was difficult for believers to stand up for such a long time. However, despite the reduction, Vigils were still celebrated in the evening, so it seems natural that the Matins should also be held in the evening as part of the All-Night Vigil, which, in fact, is not a bad thing.
Translated by The Catalogue of Good Deeds