This past February, Dick Costolo did something smart: He shut down his startup, Chorus, even though, at less than a year old, it had real customers and money in the bank.

Costolo, the former CEO of Twitter, had hoped that Chorus would help motivate people to exercise by signing them up into teams of friends. The problem, he said, was that instead of encouraging people to stay committed to their workouts, the presence of a support group meant that if anyone slacked off, the app actually made the person feel guilty--so he or she wouldn't use it. Psychologists call this the abstinence violation effect. Alerts about a team­mate's progress didn't motivate people to use the app--on the contrary, they just made them feel bad.

To my mind, Chorus gallops out as the first horseman of the coming Notification Apocalypse: the overuse and overdependence on notifications, reminders, and prompts in consumer software and apps to encourage users to do some­thing that they really may not want to do. Too many companies rely on an alert's popping up on a mobile screen without thinking through whether the message--or the product or the company--is one that people actually want. For many of these firms, a reckoning is sure to come.

Notification abuse is just one example of a larger challenge among so many new tech companies--companies that have seized on the latest hacks of human psychology and the pseudo­­science of A/B testing to create highly optimized, highly manipu­lative products. These hacks typically come in the form of user experience, or UX, fads: progress bars or gamification badges or status points. At best, these fads seem like a benign and fun way to beguile users into certain behaviors.

But when your company is trying to manipulate consumers into doing something, human psychology is just as likely to work against you as for you. Costolo quickly spotted some­thing that many startups are too slow to recognize: Humans behave in strange ways. Woe to those companies that think they can bend our brains to their benefit.

This is surely the case with gamification, which five years back was seen as the secret to luring consumers into all sorts of behaviors. Badges and tokens were everywhere, rewarding you for checking in (Foursquare) or checking out (Expedia). Alas, badges and tokens are no substitute for satisfying human needs for novelty and utility. Gamification has been so misused that the entire shtick is exhausted.

And now there's the latest fad: scarcity. Mastered by the hotel site, scarcity dangles supposedly dis­appearing offerings, such as hotel rooms, like they're apples from Eden. Amazon, Airbnb, and others insert little prompts that hint at dwindling inventories or fast-approaching expiration dates that compel us to buy now, lest we miss out.

Many companies are abusing scarcity--maybe I should call it scare-ity--by using sketchy numbers or arbitrary deadlines. EBay, for instance, often invokes scarcity by labeling some products as "almost gone" without noting a deadline or the number of remaining units. This is pure manipulation, and it's not only unfair, it's ultimately self-defeating. "People don't like to be manipulated, and they'll find out eventually," says David Teodorescu, a UX designer and writer who has analyzed the psychology of scarcity. "Scarcity taps into a psychological bias we humans have, but companies and designers need to use it ethically. It's much easier to lose trust than to build it."

Those mind games never work for long; people get wise. It's time for a new crop of startups to recognize that--and to exploit it.