Why do scammers frequently call their products a "system"?

Marketing, sales and all persuasive measures often borrow terms from science and other well respected fields, say business, to show their claims in the best light. Doing so prevents or puts off more careful analysis. Con artists, being most desperate of these salesmen, use the best analytical verbiage they can manage.

A System has the benefit of being made up of many parts. So if one part is suspect it can be claimed to be corrected by some part as yet unspecified. It's very complicated you see.

Remember, for each word you hear that alerts you to the lie fifty other people are ready to buy it because of that same word. Education is slow and people are many.