[amaccuish]

The fact that it lay undetected for 17 years, and was able to use the webcams of those infected.

[ashleyn]

Part of the reason it lay undetected was that he was using it primarily for child exploitation, and not for financial gain, which is typically how evidence of malware rapidly turns up.

[gbersac]

Child exploitation is not true. He was spying people, not especially children.