When you communicate something is singular, the more effective people believe that thing is.
David Abbott, the legendary copywriter and co-founder of Abbott Mead Vickers BBDO, used this tennis ball trick a lot with clients.
David used this trick to encourage clients to focus their messages on ONE selling point.
In Psychology, there's this concept called The Goal Dilution Effect.
It's a fascinating concept that can change how you think about brand positioning and copywriting.
Six experiments from Zhang, Fishbach & Kruglanski show that when you try to communicate more than one benefit, the less impact your message has.
That's why when a brand claims it does ONE thing really well, people assume that brand is very good at that thing.
But if a brand claims they do many things really well, consumers tend to think that brand doesn't really do anything that well.
So if an American wine online shop claims it helps wine lovers "discover the best artisan wines New Zealand has to offer", people will just assume that the selection of quality wines is much better than an American Online Liquor Store that sells whisky, rum, vodka and a bunch of other alcoholic drinks including (New Zealand) wines.
Here's another classic example.
Ever wondered how Google became so successful?
When Google launched in 1998, all major competitors were trying to become portals. And their home pages looked super cluttered.
But Google was the exact opposite, from day ONE.
Google was just a simple and clean search engine.
Google focused on being an exceptional search engine – And nothing else.
The more messages you try to communicate, the less you'll persuade.