Plenty of products people buy once and never think about again. A few they reach for without deciding to. The gap between those two outcomes is rarely about the product being twice as good, it is usually about three quieter levers a brand can pull: what you bundle together, what you keep exclusive, and how you turn a purchase into a habit.

The quick version

  • Bundling sells several things as one package. Done as mixed bundling (parts available separately too), it raises what customers spend and smooths out who-values-what, not just a discount trick.
  • Exclusivity makes an offer feel more valuable by limiting who gets it or when. It works because scarcity changes perceived value, but fake scarcity is quickly seen through.
  • Stickiness comes in two flavours: habit (the customer wants to come back) and lock-in (it is costly to leave). Habit is the durable one.
  • All three can be used to serve a customer or to trap one. The serving version is the only one that compounds.

The idea in depth

Each lever has a real body of theory behind it, and each has a failure mode that shows up the moment you treat the tactic as a free lunch. Take them one at a time.

Bundling: more than a discount

The economics here are older and sharper than most marketing advice. In 1976, William Adams and Janet Yellen published Commodity Bundling and the Burden of Monopoly in the Quarterly Journal of Economics, and laid out why selling things together can earn more than selling them apart. Their key distinction still organises the field: pure bundling means you can only buy the package (cable channels you cannot unpick), while mixed bundling lets customers buy the bundle or the parts on their own.

The reason bundling works isn't mainly the discount. It is that customers value the components differently, and bundling smooths those differences out. One person loves the software but shrugs at the support plan; another is the reverse. Bundle them at a sensible price and both buy both, because the package looks fair to each even though they value the pieces in opposite ways. Adams and Yellen showed this lets a seller capture value that separate pricing leaves on the table.

So the practical move: before you bundle, sketch who values which component and by how much. If your customers value the parts in different orders, a bundle will likely lift revenue. If everyone ranks them the same way, a bundle mostly just gives away margin, and you should price the parts separately instead.

There is a second, strategic use the marketing books often skip. Barry Nalebuff has shown that bundling can also work as an entry barrier: a company strong in two products can package them so a rival selling just one finds it hard to break in (Nalebuff, Yale ICF working paper, 1999). That is the same logic that draws antitrust attention, which is the honest limitation: bundling that exists to box out competitors rather than to serve customers can cross a legal line, and what counts as fair varies by jurisdiction, worth a check with counsel before you build a strategy on it.

flowchart LR
  A(["Two products,
customers value
them differently"]) --> B{"Same ranking
for everyone?"}
  B -- "Yes" --> C(["Sell separately,
a bundle just
gives away margin"])
  B -- "No" --> D(["Mixed bundle:
package + parts
both available"])
  D --> E(["More customers
buy more,
value captured"])
A quick test for whether a bundle will earn its keep. Leaders Loop

Exclusivity: scarcity that is real

Exclusivity is bundling's mirror image, instead of adding more, you fence some off. The behavioural engine is Robert Cialdini's scarcity principle, set out in Influence: The Psychology of Persuasion (1984): people place more value on what is limited or harder to get. Cialdini's line is that opportunities seem more valuable when their availability is restricted, partly because we dislike losing options and partly because scarcity is a rough signal of quality.

Exclusivity comes in three honest forms: time ("the cohort opens in August"), quantity ("ten seats"), and access (invitation, membership, a tier earned rather than bought). Each raises perceived value without changing the product itself.

What to do with that: pick the form of scarcity that is true for your business. If you genuinely run small cohorts, say so and let the small number do the work. If a feature is genuinely members-only, gate it cleanly rather than dangling it at everyone.

The limitation is blunt and worth stating plainly: manufactured scarcity backfires. A "only 2 left!" banner that resets every page load, or a "final hours" deadline that never actually arrives, trains customers to distrust you, and that distrust outlasts the short-term bump. Scarcity borrows against your credibility; fake scarcity spends it and never pays it back. Use it only where the limit is real.

Stickiness: habit beats lock-in

Stickiness is the prize the first two levers are aiming at, but it splits into two very different things, and confusing them is where a lot of "retention strategy" goes wrong.

The first is lock-in, switching is costly, so people stay. Carl Shapiro and Hal Varian's Information Rules (1999) is the clearest treatment: once a customer has learned your system, migrated their data, or trained their team, the total cost of switching can be high enough that they stay even when a rival is a little better. Lock-in is real and it is valuable, but it is loyalty that runs out the moment the switching cost drops, and it quietly invites someone to come along and pay that cost for the customer.

The second, and the durable one, is habit, the customer comes back because returning has become automatic, not because leaving is painful. Nir Eyal's Hooked (2014) gives the working model: a Trigger (internal or external) prompts an Action, which yields a Variable Reward (the small uncertainty that keeps it interesting), after which the user makes an Investment, adding data, content or a connection, that makes the next loop easier and the product more theirs. Run that loop often enough and the behaviour moves below conscious decision.

That this is even possible is well grounded. Behavioural scientist Wendy Wood, drawing on three decades of research in Good Habits, Bad Habits (2019), estimates that roughly 43% of what people do on a given day is repeated in the same context, largely without deciding to. Her finding for product builders is specific: habits form when the context makes the behaviour easy to repeat and the behaviour is rewarding. Friction is the enemy of habit; a cue plus an easy, rewarding action is the recipe.

Lock-in keeps customers who would leave if they could. Habit keeps customers who could leave but don't want to. Only one of those is a compliment.

So the move is: spend less effort raising the exit cost and more on shortening the loop. Find the customer's natural trigger, make the rewarding action take seconds not minutes, and give them a reason to put something in (a saved setting, a profile, a small win) that makes their second visit better than their first.

The honest limitation, and Eyal himself presses this, is ethical. The same loop that builds a genuinely useful habit can build a compulsive one. A model that works equally well on a budgeting tool and a slot machine is a model that needs a conscience attached. The test he offers is simple: would you use it yourself, and does it measurably improve the user's life? If the honest answer is no, you are building a trap, not a habit.

flowchart LR
  T(["Trigger
(internal or
external cue)"]) --> A(["Action
(easy, low-friction)"])
  A --> R(["Variable reward
(a little
uncertainty)"])
  R --> I(["Investment
(data, content,
a small win)"])
  I -.->|"makes next
loop easier"| T
Eyal's Hook: each pass through the loop lowers the friction on the next. Leaders Loop

A worked example

The figures below are illustrative, a composite to show the levers in motion, not a real company's numbers.

Imagine a small SaaS tool for freelance designers, call it Easel. It sells a drawing app for £12/month and, separately, a stock-asset library for £10/month. Sales are flat. The team pulls each lever in turn.

Bundle. They notice their two customer types value the parts in opposite orders: illustrators love the app and barely touch the library; layout designers live in the library and treat the app as a nice-to-have. Textbook conditions for a mixed bundle. They keep both products on sale separately, and add an "Easel Pro" package at £18/month, less than £22 for the pair, more than either alone. Both customer types now find £18 fair, because each is getting their must-have plus a useful extra. Average revenue per account drifts up, not down, because they sold more rather than discounting.

Exclusivity. Pro subscribers, and only them, get early access to each month's new asset packs, a real access-scarcity that costs Easel nothing to grant. It makes Pro feel like a club rather than a price tier, and gives the free-app users a concrete reason to upgrade.

Stickiness. Here the team resists the lock-in reflex (no "export is disabled on the free plan" cruelty) and builds the Hook loop instead: a Monday-morning email showing three new assets in the user's saved style (trigger), a one-click "add to my library" (easy action), a rotating set of fresh packs so it is never quite the same twice (variable reward), and a "favourites" board the user curates over time (investment). By month three, opening Easel on Monday is just something designers do, and the board they have built makes leaving feel like abandoning a workspace, not paying an exit fee. The stickiness is a by-product of usefulness, which is the only kind that lasts.

Frequently asked questions

Is bundling just a discount by another name?

No, and treating it as one is the common mistake. A discount lowers margin to win price-sensitive buyers. A well-built mixed bundle raises total spend by getting customers to buy components they would otherwise have skipped, because the package looks fair to people who value the parts differently. If your bundle is only ever cheaper than the sum with no change in what people buy, you are discounting, not bundling.

Doesn't exclusivity just shrink my market?

It can, which is why the form matters. Time and quantity scarcity create urgency without permanently excluding anyone, the cohort reopens, the next batch ships. Access scarcity (membership tiers, invitations) does fence people out, but it raises the perceived value of being inside. The trap is using exclusivity you cannot back up; real limits build value, invented ones burn trust.

What is the difference between stickiness and lock-in?

Lock-in is stickiness imposed by cost, leaving is expensive, so people stay. Habit is stickiness earned by value, returning is automatic, so people don't want to leave. Both retain customers, but lock-in evaporates the moment a competitor lowers the switching cost, and it leaves customers resentful. Habit is the version that survives a better-priced rival.

Is building habit-forming products manipulative?

It depends entirely on whether the habit serves the user. The same Trigger–Action–Reward–Investment loop powers a meditation app and a gambling app. The honest test, which Eyal himself uses, is two questions: would you use it yourself, and does it genuinely improve the user's life? If yes to both, you are reducing friction on something worth doing. If no, you are engineering a compulsion.

Which lever should a small business start with?

Usually stickiness through habit, because it has the lowest cost and the longest payoff, and it does not require market power. Look at what your best customers already do repeatedly, find the cue that triggers it, and remove every second of friction from the action. Bundling and exclusivity work best once you have a returning base to apply them to.

Related in the Toolkit

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