Advertising is prey to lots of different fashions. A tendency to focus on stunts that will have no impact on the real world is one of them. Putting preaching ahead of practice is another.
One fashion that ebbs and flows is that of the endline. Although, to be honest, it's a fashion that tends to ebb rather more than it flows. Endlines aren't in vogue. And they haven't been for many years.
That perhaps explains why so many of the great endlines date back at least a decade, if not to the last millennium. Examples include "Vorsprung durch technik", "Just do it", "Every little helps", "Have a break", "Dirt is good", "I'm lovin it", "The power of dreams", "You're not you" and so on.
Just because, like polo necks, endlines aren't as fashionable as they once were, doesn't mean they're any less valuable. And the reason for their value is simple. They help you own a thought, a purpose, a belief, a competitive advantage in the mind of your customer, making it inseparable from your brand. The advantage this confers is eulogised by Ries and Trout as the Law of Focus: "The most powerful concept in marketing is owning a word in the mind of the prospect."
What is so telling about the endlines I've cited above is that we all know who they're for without the brands being mentioned. Our minds join the cognitive dots. This kind of mental availability was always gold dust and, in our hyper-fragmented media world, has become more precious than ever.
Of course, like all precious things, endlines don't come easily. The level of distillation and compression they demand requires considerable intellectual effort and, yes, a fair amount of luck. Even when you've got a contender, it will take sustained investment over two to three years before it begins to establish itself. Without wishing to sound cynical, how many of the agency team are going to be on the account when the line begins to bear fruit? Might it be more tempting to do a one-off show-stopper that garners rather more headlines and plaudits in the short term?