The trap I see this happen constantly. Someone's built one thing. It works. Revenue's coming in. Then they start thinking about what else they could sell. Maybe it's a natural extension. Maybe they've had customers ask for it. Maybe they just see money on the table and want to grab it. Then they expand. And suddenly their operation gets more complicated, their focus splits, and they're managing two separate problems instead of one solved problem. The thing is, expansion isn't always wrong. But it's almost never as simple as it looks from the outside. Why people actually expand I've sat across from people who've done this well and people who've done it badly. The successful ones weren't motivated by the same things as the failures. The failures expanded because they were bored, or because they thought they should, or because a customer asked and they couldn't say no. The successful ones expanded because they had a specific problem they'd solved, and they'd figured out exactly how to apply it elsewhere. There's a difference between opportunism and strategy. One feels exciting right now. The other feels boring until it works. I've watched people running small teams in London and beyond make this call. The ones who get it right usually have three things in common. They know their margins on the new thing before they start. They understand what it'll cost them operationally, not just in cash but in attention. And they've already maxed out what they can do with what they've got. The real cost of complexity Here's what most people don't calculate: the hidden cost of a second product line is not linear. If you're running one product well, you've built systems. You know your supply chain. You know your customer. You know how to market it. Add a second product and you don't just add 50% more work. You add new suppliers, new quality control processes, new marketing channels, potentially new customer segments to understand. You've got to manage inventory for two things instead of one. If one product has seasonal demand and the other doesn't, you're now juggling cash flow across two different cycles. I worked with someone who made bespoke leather goods. They were doing well. A customer asked if they could make the same items in canvas. Seemed simple. Canvas is cheaper than leather. Faster to work with. Easy money, right? Six months in, they'd lost 35% of their leather business because the canvas customers were a different type of person with different expectations. They were also managing two separate production schedules, two supplier relationships, and marketing to two audiences. They made less money overall and worked harder. They eventually dropped the canvas line. Should have never added it. When expansion actually makes sense There are genuine reasons to add a product. But they're specific. You've maxed out growth in your current market. You've hit the ceiling. You can't make more money selling the same thing to the same people, so you need something new. You've got a product that naturally leads to another one. Not because you think it does, but because your actual customers are telling you they need both and they'd buy from you if you had it. And you've validated that at least 20 of them would actually pay for it, not just said they would. You've got operational capacity that's genuinely unused. You're running at 60% utilisation. You've got time and resources sitting idle. Adding a second product that uses the same infrastructure makes sense. You've spotted a way to solve a problem you've already solved, but for a different audience. And you can do it with 80% of the same systems you've already built. Notice what's missing from that list: because a customer asked. Because it seems like an easy add-on. Because you're bored. Because you think you should. The framework Before you add anything, answer these questions honestly. First: what's your utilisation rate right now? If you're not at least 75% utilised in your core business, expanding is a distraction. You've still got room to grow what you've got. Second: how much of your current infrastructure can the new product reuse? If the answer is less than 70%, the complexity cost is too high. You're essentially building a second business. Third: have at least 20 actual customers (not prospects, actual customers) specifically asked for this? And have you had a conversation with them about price? Not a vague conversation. A real one where you quoted a number and they didn't balk. Fourth: what's your cash position? Expansion costs money upfront. You won't see returns for at least six months. Most people underestimate this by 40%. Can you genuinely afford to be wrong? Fifth: can you describe what success looks like in a single sentence? If you can't, you don't understand the expansion well enough to attempt it. I've found it useful to run through this with a Decision Matrix, just to force yourself to score each factor properly instead of letting your gut drive the decision. ALIRA's tool does this well if you want to structure it formally. The geopolitical angle you haven't considered There's something happening right now that's making expansion riskier. Energy costs are volatile. OpenAI's paused their UK data centre deal over regulation and energy costs. Supply chains are fragile. If you're thinking about expanding into something that requires new suppliers or new logistics, you're betting on a stable environment that might not exist in six months. Lidl's opening 50 stores this year. They can absorb that risk. You can't. So if your expansion depends on stable energy costs or predictable import duties, think twice. What to do this week Write down the product or service you're thinking about adding. Then answer those five questions above. Spend 30 minutes on this, not five minutes. Most people rush it. If you get to question three and you can't name 20 customers who've asked for this, stop. You don't have a product expansion. You have an idea. Ideas are cheap. If you get through all five questions and it still looks good, talk to someone who's not invested in the decision. Not a mentor who'll encourage you. Someone who'll push back. That conversation will cost you 90 minutes and could save you six months of wasted effort.