Answer:
The answer is extrinsic and intrinsic factors.
Step-by-step explanation:
Extrinsic factors refer to any sort of motivation that does not come internally from a subject. It might be having a reward such as money or, in the case of cyberstalking, maybe social acceptance.
Intrinsic factors are related to the subject's physiological or pathological needs. In the case of cyberstalking, it is possible for someone to engage in it because of deep psychological issues, maybe as a sort of impulse.
The text implies that it's difficult to know the exact motivation for this kind of behaviour because both factors come into place.