It was sinless until Eve transgressed. James 1:14-15 says " But each person is tempted when he is lured and enticed by his own desire. 15 Then desire when it has conceived gives birth to sin, and sin when it is fully grown brings forth death." It's us not God.
God wanted people to have free will to chose to listen or not listen to God's wants and could have made if where people where incapable of sin, but then free will would be impacted. Also, sin can be a grindstone to polishing the soul through the challenge of overcoming it and result in a stronger, better soul. God also has allowed the devil to run course for a time.
He didn't want to make us robots, what's love when it's forced on us? So he made Adam and Eve and gave them one order, they can have everything in the garden, just not the fruit from the forbidden tree. But they made a mistake and ate it, causing the earth to be sinful. But God sent his only son to die on the cross for us, because if we were all going to go to hell because of their mistake. God is going to come to earth one day and judge the living and the dead. We have a choice, we can go to heaven or we don't, God isn't going to make us love him because that wouldn't be true love if in reality that's not what we would've originally wanted.
Trying to comprehend the divine is like trying to taste sound. I can't imagine anyone here could speak for God. I suppose it depends on which god you are referencing as well. Since the "G" was capitalized, I assume that'd be the Abrahamic God. According to the bible, He allows sin for the purposes of free will. But I'm not God, so I don't know for sure.
Why did God make sin in the first place? Well according to the King James Bible, the short and often confusing answer would be, "So that we could be like God". Now at first glance, the question being asked paired with that short answer seems illogical, but the longer version (panoramic Biblical view) explains it better if you have the mind and time for it. I guess a reasonable answer would be that of a comparison... What creation/creature that God creates could ever compare to God since it would NOT be the God that created it? It would have to be lesser by comparison. Lesser don't get you seated next to God on the throne as the book of Revelation suggests. Adam, Eve, etc., etc., even though without sin up to certain point, were still non-the-less lesser... They were NOT equal to God. Do you think that the trees in the garden were a mistake? The story is that we were actually meant to eat from both... but most people won't go so far as to analyze that. They never get that far in their search of Biblical knowledge.
Romans 5:12 says "That is why, just as through one man sin entered into the world and death through sin, and so death spread to all men because they had all sinned." So God didn't create sin.. But man created it.
We live in a troubling world don’t we? And we can see in the wonderful creation around us that God does care for us. In fact 1 John 4:8 says “God is Love”. This harmonizes with the start He gave the first couple. He put them in paradise, with rewarding work and perfect health (Genesis 1:26-28). In fact, after he completed his creative works he declared everything to be “very good” (vs 31). In other words, his creation met his high standards of excellence (Deuteronomy 32:4). Because he made humans with free will He had the right as the Sovereign and Creator to see where their loyalty stood. They deliberately disobeyed a divine command, which was the beginning of “sin” and led to their death and ours (See Romans 5:12). However this did not mean that God’s purpose for humans, to live in peaceful conditions on a beautiful earth, would not be fulfilled. God guarantees this with the gift of his Son (John 3:16, Matthew 20:28, Acts 17:31) and his word (Isaiah 45:18, Isaiah 55:11, Psalm 37:9-11, 29). So he cares very much for us. Please follow this link to a brief video to learn more: http://www.jw.org/finder?locale=en&docid=502013341