The meaning of the word 'obstacle' is:
1. An object that stands in the way (and must be removed or surmounted or circumvented). 2. Something immaterial that stands in the way and must be circumvented or surmounted: "lack of imagination is an obstacle to one's advancement"; "the poverty of a district is an obstacle to good education".
http://ultralingua.com/onlinedictionary/index.html?service=ee&text=obstacle
That which stands in the way, or opposes; anything that hinders progress; a hindrance; an obstruction, physical or moral.
(Please note the word 'moral').
http://www.onelook.com/?other=web1913&w=Obstacle
History speaks of many persons suffering from unsurmountable
obstacles - all of them are not supposed to be challenges. Many accept
them as fate and go through suffering. Some feel that they have the
will power to overcome. I wish to know how many of you could
overcome them to become examples for others.