Reasons for Safety Concerns
The concept of developing super AI was previously unimaginable. Impossible is nothing or at least not everything, and the credit for this goes to recent discoveries. What seemed impossible about five years back does not exist any longer as many of the goals have already been accomplished relatively seamlessly.
Due to the potential of AI going ahead of its time, there is no way to ensure how prudent its behavior can be. Precisely, technological developments should not go past the standard interpretations of human beings as they are and will eventually be one of the smartest creatures of nature.