The reason the English settled in Roanoke was to expand England, and to get gold and other riches. Another reason was because several people on the trip, came for religious freedom and a better life.
One of the problems the Roanoke colony had was not having enough food, and several people died because of the small to no amount of food. Another problem the Roanoke colony had was having low supplies.
What I think the solution would be (which is what happened) is to sail more supplies and food, but when that happened in real life, the delivery was delayed because of a war going on in England, so the supplies came 3 years late. When the settlers came to Roanoke with the supplies though, they were gone with only leaving "CROATOAN" carved on a tree.