George has sold a lot of grills with late-night infomercials and there are two reasons his infomercials run predominantly on late-night television.

The obvious one is that there are more of what TV people call "avails" (available time periods for him to buy) late night, but the second reason is one you would do well to think about if you are running a Pay-Per-Click campaign for your website.

Late night TV viewers are typically uninvolved. That means they are not engaged with either the show they are watching or some other activity. Yes, many simply can't sleep. By not being involved or connected to another activity, they are more likely to respond to a direct solicitation to buy a product.

If that same infomercial came on while the viewer was helping the kids with homework or working on a report for work, it would take a much higher level of persuasion for the show to get the viewer to disconnect from that activity and pick up the phone and buy a grill.

What does this have to do with your website? Simple. Look at your Pay-Per-Click results. There are probably clear patterns in the conversion rate of your clicks. At different parts in the day, your prospects may be searching more purposefully than others. With some PPC campaigns we've seen, the trend is the opposite of the TV infomercial patterns. Late-night searchers can be less serious, less involved in their searches, perhaps because they have more time at hand.

Daytime searchers for some campaigns we've seen are more purposeful, seemingly more pressed for time. So the clicks in the daytime were converting higher than the late night clicks.

If you are just looking at your overall results, you may be missing a trend such as the one I've described. Your Google Ad Words account lets you daypart your campaign so your ads only run during those times that are meeting your conversion goals.

If you are going to daypart though, stay on top of it. Holidays are big opportunities for many Pay-Per-Click campaigns, and search activity (like TV watching) is different on holidays than non-holidays. So you simply can't set it and forget it.

And if the company that handles your PPC isn't up to speed about dayparting, now is a good time to "grill" them about the practice.