The vast majority of people who make money do it in the field in which they have the most training and experience. Those who lose it usually do so in an area they know little about. It's one thing to speculate with money you can afford to lose and quite another to lose money that literally belongs to another. It doesn't necessarily mean that the investment should be paid in total, but it does mean that the down payment should not be borrowed. Otherwise, you are presuming on an uncertain event.
Utility simply means buying something of use to someone else.
The promoter urges the potential buyer to act quickly before the opportunity is missed. The exact technique will vary, depending on the need. It may be pressure to become a success, to avoid income taxes, or to make it for retirement. Once the money has changed hands, the promoter knows it's too late to back out. The final ploy is to develop an attitude of covetousness by hinting that another prospect is waiting to snap up the deal.