Don't teach your students as if they are a monolithic population of learners. They learn differently, they have different goals, different skills, different backgrounds.
Don't sell to your customers as if they are a fungible commodity, a walking ATM waiting for you to punch. Six of one are not like half a dozen of the other. They tell themselves different stories, have different needs and demand something different from you.
Different voters, different donors, different employees--we have the choice to treat them as individuals. Not only do they need different things, but they offer differing amounts of value to you and to your project. The moment your policy interferes with their uniqueness, the policy has cost you something.
We used to have no choice. There was only one set of data for the student body, one way to put things on the shelf of the local market, one opportunity to talk to the entire audience...
One of the biggest unfilled promises of the digital age is the opportunity to go beyond demographics and census data. Personalization wasn't supposed to be a cleverly veiled way to chase prospects around the web, showing them the same spammy ad for the same lame stuff as everyone else sees. No, it is a chance to differentiate at a human scale, to use behavior as the most important clue about what people want and more important, what they need.
It's a no-brainer to treat the quarterback of the football team differently from the head of the chess club. We treat our bank's biggest investor with more care than someone who merely wants to trade in a bag of pennies. Instead of reserving this special treatment for a few outliers, though, we ought to consider what happens if we offer it to all of those we value.
The long tail of everything means that there's something for everyone--a blog to read, a charity to donate to, a skill to learn. When you send everyone the same email, demand everyone learn from the same lesson plan or try to sell everyone the same service, you've missed it.
A very long time ago, shoe salespeople realized that shoes that don't fit are difficult to sell, regardless of what you've got in stock. Today, the people you serve are coming to realize that like their shoe size, their needs are different, regardless of what your urgent agenda might be.