Agreed with the sentiment that there are different kinds of clients/opportunities and sales cycles. However the idea specifically in ABC is the 'close'. 'Closing' is the act of securing payment from an entity. I've seen a lot of 'sales guys' who talk about how hard they're selling. But ultimately getting the money into your bank account is the real goal. Everything else is derivative.
Loosely quoting Eli Goldratt, "Until the money is in your bank account and there is no possibility of having to refund it to the customer, you have not made the sale."
