In this particular sentence, "reason" is not redundant. It is the object of the sentence. "Security and privacy" are modifiers of the word "reasons."
You can write a different sentence with "security and privacy" being the objects.
The difference in meaning is subtle, with the first sentence being about "reasons" and the details thereof, and the other directly about "security and privacy."
Also, instead of a comma between the two independent clauses, a semicolon should be used, or better, a period after the first.