Normally, ads aren’t supposed to have much text. People won’t sit and read a full paragraph, and especially not in print that small. 6-10 words is the recommended limit for ads, and indeed, most of the ads on my Kindle are more along the lines of “Tempest: The new album by Bob Dylan. Pre-order today!”
But most ads on my Kindle are forgetting one important thing: these ads are going to be appearing on a Kindle. Which is to say, a device designed for reading lots and lots of small text. I read 10,000-word blog posts and 260,000-word novels on this thing. A paragraph of text isn’t going to bother me at all. And by recognizing that, Wells Fargo has gained their ability to take their time. They don’t have to be abrupt and forceful (Buy this thing! Now!)… they can take their time. Set a friendly tone. Be a little poetic (which is also likely to play well with Kindle readers).
You may not advertise on Kindles, or even buy paid ad space at all. But the lesson remains the same for any medium and any promotional method: remember who you’re talking to. Make something they’ll like.