Contrary to what I've heard people say all of my life, attention span isn't any shorter now than it has been for generations. People have always loved information given to them in a short, concise way. Just think of something set to a rhyme and you know what I mean. Look at an ad in a newspaper from 100 years ago - the same system has been in place for a long time. It starts with a headline, and possibly an image, then a subhead, then more text explaining. Human nature being what it is, and has always been, we glance, absorb what we think we understand from the headline, and then move on.
Information that sounds too good to not be true sometimes isn't. But the marketing people are counting on you swallowing it before you question it, or even do any research on it. With any luck, you will repost or retweet it. Every once in a while I see something like this:
Chevrolet tried to sell a car called the Nova in Mexico. But Nova means *don't go*, so it failed.
It's easy enough to find out that this isn't true. The Nova sold well in Mexico. But it sounds too good to not be true. And this little bit of silliness won't hurt you. But if you start believing in stuff like this, and it makes you buy things without doing any research, it will.