When I can't sleep, I sometimes check out the long-form commercials we dress up with the term "infomercial." Of course, advertisers who invest in these expensive commercials try to put their products in the best possible light, and that's fine. But sometimes the people they hire to write the ads decide that the correct word for the context just isn't showy enough. They want a substitute. Something fancier or more sophisticated. That's okay, but it's best if the copywriter knows that words that are similar don't necessarily mean the same thing. Choosing the wrong word can make an ad sound stupid rather than upscale.
The best example I've seen lately comes from a product I can't even remember because I was laughing so hard at the substitute word the copywriter thought was more elegant than the correct one. The commercial said,"If you are missing the restive sleep you need, we can help."
Unfortunately, by substituting the word restive for the correct word--restful--the copywriter really screwed up and undercut the client's message. Restful, of course, means tranquil, giving rest, or a feeling of rest.
Restive, which the copywriter would have discovered had he or she bothered to look it up, means restless, impatient, or difficult to control. So if you're not awake enough already, go ahead and try the product. It's guaranteed to keep you up all night, tossing and turning and feeling out of whack.
Somehow I don't think that's what the advertiser had in mind when he hired an ad agency to tout his sleeping aid. Because the copywriter was too lazy to do the job, the client poured money down a rathole. Too bad.