I had a site which was doing pretty badly. I applied my new SEO tactics and look what happened:
This is the part where, if I were a conniving guru, I would say the following:
"You should buy my SEO/Traffic service for the low low price of $97/month - because look what I did for this site! I brought its traffic up by 2800% in one month! At that rate, if you are getting 100 visitors per day, I can get you up to 2800 per day!"
Why do I say "conniving" guru? The screenshot is real (the numbers aren't doctored at all), and there wasn't a single lie in that sales pitch.
BUT here's the catch:
All I did was bring the traffic up from about 4/month to 116/month.
Be very aware whenever you see gurus using percentages to describe their success. Look at the real numbers. And watch out when they say things like "at that rate" - that usually means that the "rate" to which they are referring is not typical.