Mate, my explanation goes like this, if a new developed crypto is created the choice of the founder or creator depends on Him if He would like to reveal His Identity for less security of how much he own of His own crypto, my point is, nem is knowledgeably made by a group of developers and the safetiness depends on who Holds or own it, Hackers will not attack a specific area specifically NEM of they don't have the ability to do it and the availability of transparency of the owner of the NEM.

simple explanation, crypto currency is safe, the idea of losing it because it was stole by somebody is the idea of unsafetiness because there are hackers, who keeps on lurin around making ways to initiate the thing they want to get. the problem is, Hackers are very smart, if they are untraceable it means that things happen in incognito mode.
(Leaving with no History)