Why did Alexander the Great head home instead of continuing to expand his empire?

First, his father was able to unite the Greek city-states, and Alexander destroyed the Persian Empire forever. More importantly, Alexander's conquests spread Greek culture, also known as Hellenism, across his empire. ... Without Alexander's ambition, Greek ideas and culture might well have remained confined to Greece.

Explanation:

it is a better alternative

productive most commonly means: achieving or producing a significant amount or result.

explanation:

productive can also mean:

these depend on how the word productive is used. most likely productive will mean   achieving or producing a significant amount or result.