You may not be using the beaker from high school, but be sure to test your ads to make sure that they are performing at their best. Decide on a few metrics to measure (probably click-through rate and conversion rate), and see what happens when you try different things. If you lower the cost-per-click bid, does your conversion rate increase? If you use different keywords or even just different matching, what is the result? What about different ad texts, even something as simple as changing the capitalization. You may expect your results to be one way but surprises happen.
In one experimental test we conducted, we decided to pay a little less on each ad, in the hopes of making a bit more profit. The ad position decreased from first to third and the click-through rate also declined, probably because viewers didn’t pay as much attention to it. But surprisingly, the clicks we did get were much more likely to make a purchase. As a result of the small experiment, we found a way to save money on AdWords budget and end up with more sales, a win-win situation.
Of course, some markets may behave differently. If you are advertising lesson plans for teachers, you probably will not see good results for misspelled advertisements, even if the person mistyped the search term. Other customers might not mind the misspelling and who knows, you might even get better results with it. The only way to discover what happens is to test out different combinations and see what happens. And of course, it will help if you can put yourself in the shoes of the audience, and the only way to do that is to research the product or service offered until you understand why people would buy this widget in the first place. Insight + experimentation = more successes and more profit for both the marketer and the end-client.
For more tips on running AdWords campaigns, check out AdWords University: The Complete Guide to AdWords.