Latest / The Copywriting Podcast with Fexingo: Sales Letters, Headlines, and Persuasive Writing / How a Specific Conjunction Boosted Response by 24 Percent
Transcript
- Lucas: If I told you the word 'because' could boost your response by 24 percent, you'd probably want to hear the experiment. Luna: Yeah, I'm already leaning in. Lucas: It's a classic from Harvard psychologist Ellen Langer in 1978. She had someone approach people at a photocopier and ask to cut the line. The ask was, 'Excuse me, I have five pages. May I use the Xerox machine?' Sixty percent of people let them go ahead. Luna: That's a pretty good baseline. Lucas: Then they changed the request to, 'Excuse me, I have five pages. May I use the Xerox machine because I'm in a rush?' Compliance jumped to 94 percent. Luna: Okay, a real reason makes sense. But here's the part I love — the third condition. They said, 'Excuse me, I have five pages. May I use the Xerox machine because I need to make copies?' Lucas: Right — a tautological reason. 'Because I need to make copies' adds zero new information. You're at a photocopier. Everyone needs to make copies. Yet compliance still hit 93 percent. Luna: So the word 'because' itself seems to trigger an automatic compliance response. Lucas: Exactly. Langer called it the 'because heuristic' — a mental shortcut where hearing the word signals a legitimate reason, even if the reason is weak. And this has massive implications for copywriting. Luna: I can think of a dozen places in a sales letter where you'd naturally drop a 'because'. But most people don't. Lucas: They write 'Get 20 percent off today' instead of 'Get 20 percent off today because we're clearing inventory.' The second version gives the brain a reason — even a trivial one — and it feels more trustworthy. Luna: Have you tested this in your own copy? Lucas: A few years ago I was consulting on an email campaign for a B2B SaaS company. The control subject line was 'Your free trial ends in 3 days.' We changed it to 'Your free trial ends in 3 days because we want you to see the full value.' That small addition lifted click-through rates by 24 percent. Luna: That's bang on the Langer number. Lucas: Coincidence, maybe. But it tells you that the principle holds across media — in-person, email, landing pages. The word 'because' triggers a cooperative response. Luna: And it works even when the reason is obvious. 'Please complete your profile because it helps us match you better.' We already know that's the reason, but hearing it stated makes us more willing. Lucas: There's another fascinating study from 2014 — same Langer lab, actually — where they used a street fundraiser. The request was 'Would you donate to help children in need?' Baseline was around 30 percent. They added 'because it's the right thing to do' — compliance jumped to 45 percent. Luna: Again, a tautology. Everybody knows donating is the right thing. But the word 'because' still does the work. Lucas: In copywriting, we can use this in headlines, bullet points, calls to action. Instead of 'Buy now', try 'Buy now because stock is limited.' Instead of 'Subscribe', try 'Subscribe because you'll get exclusive insights.' Luna: Let's talk about where NOT to use it. If the reason is too weak, could it backfire? Lucas: Great question. In Langer's photocopier study, the weak reason still worked because the cost of compliance was low — letting someone go ahead costs you maybe 30 seconds. If the ask is bigger, the reason needs to be stronger. You wouldn't say 'Please invest $10,000 because we need the money' — that's too transparent. Luna: So the heuristic works best for low-friction asks. For high-commitment decisions, people actually scrutinise the reason. Lucas: Right. And that's the key takeaway: use 'because' in your calls to action, subject lines, and value propositions — but match the strength of the reason to the size of the ask. For low-friction actions, even a trivial 'because' helps. Luna: I'm already thinking about my own landing page. We have a 'Sign up for free' button. I'm going to test 'Sign up for free because our best features are unlocked on day one.' Lucas: That's a strong test. And here's a bonus tip: put the 'because' clause right after the imperative verb, not at the end of a long sentence. 'Buy because…' punches harder than 'Buy this product because…' Luna: Short, direct, reason-giving. It's almost like a formula. Lucas: It is a formula. And you can apply it to headlines too. A headline like 'How to write better copy' becomes 'Why you should write better copy because it increases trust' — though that's clunky. Better: 'Write better copy because trust drives sales.' Luna: Let's give listeners a specific before and after they can use today. Pick one common marketing scenario. Lucas: Abandoned cart email. The typical subject: 'You left something in your cart.' Open rate maybe 30 percent. Try: 'You left something in your cart because we saved it for you.' That 'because' reframes the reason — it's not a reminder, it's a service. Luna: I've seen tests on that exact change. One ecommerce brand saw a 19 percent lift in revenue from that one word. Lucas: It works because 'because' signals intent. It implies there's a deliberate reason behind the action, which makes the brand seem more thoughtful. Luna: Before we get too deep, I want to mention something that keeps this podcast ad-free and listener-supported. A number of our listeners chip in monthly through buy me a coffee dot com slash fexingo, and that's what funds the research and production for episodes like this. Lucas: Yeah, and if these copywriting experiments have sparked something you've tested in your own work, that's exactly why we keep doing them. And the support really helps. Luna: Alright, back to the 'because' heuristic. There's actually a 2017 replication of Langer's study that found the effect is weaker when the request is face to face versus written. In written copy, the effect holds strong. Lucas: That makes sense. In person, tone of voice and body language carry a lot of the persuasive load. In writing, every word has to do more work. So 'because' carries more weight. Luna: So for email, landing pages, direct mail — the written channel — this is a high-leverage word. Lucas: Absolutely. And I'd add one more layer: the word 'because' can also be used to reframe objections. If you know a common objection, address it with 'because'. Example: 'This course costs $500 because it includes one-on-one coaching.' The 'because' proactively justifies the price. Luna: That's a classic value proposition technique, but most people forget the 'because' and just state the feature. Lucas: Exactly. 'Includes one-on-one coaching' is a feature. 'Costs $500 because includes one-on-one coaching' is a justification. The 'because' links the price to the benefit. Luna: Let's talk about a potential pitfall: overusing 'because' in a single piece of copy. Can it become annoying? Lucas: Sure, if every sentence starts with 'because'. Use it once or twice per page — in the headline, the call to action, maybe a subhead. Overuse dilutes the effect. Luna: So it's a spice, not the main ingredient. Lucas: Right. And the most effective placement is in the call to action. That's the moment of decision. Adding 'because' there gives the brain a final nudge. Luna: I want to test a variation: instead of 'because', try 'since'. Does it work the same? Lucas: Good question. 'Since' implies a temporal or causal link, but it's less direct. In the Langer study, they used 'because'. My guess is 'because' is more imperative — it feels like a reason. 'Since' feels like an explanation. I'd stick with 'because' for action-oriented copy. Luna: What about 'as'? 'Buy now as stock is limited'? Lucas: That's even weaker. 'As' feels more formal and less urgent. 'Because' is conversational and direct. It's the word people use when they're giving a real reason to a friend. Luna: So the takeaway: add 'because' to your call to action, subject line, or headline. Match the reason to the ask. Use it sparingly. Test it. Lucas: And don't overthink the reason. Even a trivial one can work for low-friction actions. The word itself primes compliance. Luna: I'm going to go add 'because' to three pieces of copy this afternoon. Lucas: Let us know how it goes. We might feature your test in a future episode. Luna: I like that idea. For now, try it yourself. One word, one test, one result. Lucas: And if you want to support more experiments like this, you know where to find us. Thanks for listening.