Why did the ancient Greeks decorate temples primarily from the outside, and the Byzantine craftsmen from the inside?

The difference between Byzantine temples with their interior decoration from ancient ones, which were often decorated on the outside, lies in the peculiarities of the ritual.

Byzantine temples are an example of Christian architecture, in which all religious rituals are held inside the temple: prayers, communion, repentance, baptism, etc.

Ancient temples are the construction of the pagan period. It is known that many temples of Ancient Greece consisted of a set of columns, as well as several rooms inside the building. That is, they actually did not have walls. This construction was due to the fact that the ancient Greeks did not enter the temple, but performed their religious rites outside, at the front door. Only priests specially trained for sacraments and sacrifices entered the ancient temple.