The correct answer to this open question is the following.
Although there are no further context and references, five reasons to move to the Byzantine Empire from Rome to Constantinople were the following.
The first reason was that Roman Emperor considered the great strategic location of Constantinopla. Byzantium had many advantages by land and by sea.
The second reason was that trade could have more chances to thrive in Constantinople.
The third reason was that Rome was in decadence. Corruption, crime, health issues. Without a doubt, Rome was not the option to maintain the capital of the Empire there.
The fur reason was that it was the last stop of the Silk Road, an important series of trade routes that connected the Empire with Asia Minor, North Africa, and China.
The fifth reason was that the Roman army could better defend the capital and display its troops to other places in a more expeditious and organized way.
