It's not just what you say that stirs people. It's the way that you say it.
A great ad campaign will make a bad product fail faster. It will get more people to know it's bad.
There is no such thing as a good or bad ad in isolation. What is good at one moment is bad at another. Research can trap you into the past.
Word of mouth is the best medium of all.
Because an appeal makes logical sense is no guarantee that it will work.
The most powerful element in advertising is the truth.