I’ll admit that Internet advertising banners are not necessarily expected to adhere to the strictest rules of spelling and grammar.
But surely if you expect me to have any interest in your “IQ Quiz,” you should at least know when to use “a” and when to use “an”… and that’s as far as I’m going to [...]

Why must people do things like this to signs?

Four commas, and not a one of them used correctly. If you’re going to invest in a sign, I highly recommend splurging on a proofreader!