These days, seeing an advertisement triggers a sort of Pavlovian response in people -- and not in a good way.
Being "sold" turns people off. Being helped, on the other hand, makes people grateful. And grateful people, typically, want to give back (i.e., do business with you).
The less advertise-y your ad is -- the less in-your-face it is -- the more people will respond to it. Because at the end of the day, people don't want to be sold.
And people want it all for free -- and giving it to them (via content marketing, for example) is a worthwhile business expense nowadays.
So remember: the best ads don't resemble ads at all. Modern companies that represent themselves without appearing like they're trying to acquire new business will come out on top every time.