The most valuable business decision is often the one you stop making. Most people can't kill a project because they're processing emotional variables as structural ones. CT10 separates them in one question.
Every founder, operator, and investor has a project they should have killed months or years ago. They know it. They can feel it. And they can't do it — because the decision to kill something you've invested in triggers a cascade of psychological resistance that has nothing to do with the project's actual viability.
The sunk cost fallacy is the most well-documented cognitive bias in behavioral economics (Arkes & Blumer, 1985). People continue investing in failing projects because they've already invested — even when they know additional investment won't change the outcome. The bias is not rational. It's not strategic. It's emotional accounting masquerading as business judgment.
CT10 eliminates the emotional variable with one question:
This is simple. It is not easy. The simplicity is the point — it strips the decision to the one variable that matters. The difficulty is emotional, not analytical. And recognizing that the difficulty is emotional is the first step to making the decision correctly.
The most dangerous sunk cost isn't money. It's identity. When a founder says "I've put two years into this," they're not making a financial argument. They're saying "this project is part of who I am." Killing it feels like killing a piece of themselves. The project has moved from the portfolio to the ego — and decisions made from ego are the most expensive ones in business. The CT10 response: the project is not you. It's an allocation of resources. Resources can be reallocated. Identity cannot be — which is why you need to separate the two before making the decision.
Once you've told people — investors, employees, your spouse, your audience — that you're building something, killing it requires a public admission that the original thesis was wrong. Most people would rather quietly bleed resources than publicly reverse a position. This is reputation management disguised as business strategy. It's also one of the most expensive forms of ego protection available: you're paying real money to avoid a temporary social discomfort.
Failing projects rarely look dead. They look almost alive. There's always one more feature, one more hire, one more quarter, one more pivot that might make the difference. This is the illusion that keeps zombie projects funded. The CT10 diagnostic: has the core thesis — the fundamental reason this project should exist — been validated? Not "are there promising signals?" Signals are decorative. Thesis validation is structural. If the core thesis hasn't been validated after meaningful investment of time and resources, additional investment isn't patience. It's avoidance.
A founder has spent 18 months and $400K building a SaaS product. It has 200 users. Monthly revenue: $3K. Growth has been flat for six months. The team is tired. The founder tells investors: "We just need to nail the onboarding flow."
CT10: If this product didn't exist and someone pitched you a SaaS business with 200 users, $3K MRR, and six months of flat growth — would you write a $400K check to build it? The answer is obvious. The only reason it's not obvious to the founder is that the $400K has already been spent, and admitting it's gone is more painful than spending another $100K to delay that admission.
The $400K is gone regardless of the next decision. The only question is whether the next $100K will produce a return. The historical investment is not evidence of future returns. It's evidence that the thesis had a chance and the chance didn't convert. That's information, not a reason to continue.
A company has four product lines. Three are profitable. One has been losing money for two years. The argument for keeping it: "It drives traffic to our other products." "We've invested too much to walk away." "It's part of our brand."
CT10: Strip to the variable. Does this product line, evaluated as a standalone investment starting today, merit the next quarter's resources? Measure the traffic claim — if Product D drives X visitors to Products A-C, calculate the revenue attributable to that traffic. If the revenue exceeds the losses, the product line is a marketing cost, not a loss. Keep it and reclassify it. If the revenue doesn't exceed the losses — which is the case more often than companies admit — the "traffic" argument is a narrative constructed to avoid the kill decision.
"It's part of our brand" is not a financial argument. It's identity attachment at the corporate level. The same bias that keeps a founder funding a dead startup keeps a company funding a dead product line. The mechanism is identical. The price tag is larger.
A 50/50 partnership was formed two years ago. One partner does 80% of the work. The other contributes the original capital but hasn't added value in twelve months. The working partner is frustrated but won't dissolve the arrangement because "we've built so much together."
CT10: If you were starting this business today, would you give this person 50% equity for what they currently contribute? Not what they contributed two years ago. What they contribute now. If the answer is no — and it almost always is — the partnership terms no longer reflect reality. The history of what was built together is a sunk cost. The question is whether the current arrangement produces the best outcome going forward.
This is one of the hardest kill decisions because it involves a person, not a product. The emotional cost is real. But the financial cost of maintaining a partnership that no longer reflects the value each party contributes is also real — and it compounds every month the conversation is avoided.
A side project — a podcast, a newsletter, a course, a community — has consumed evenings and weekends for a year. It has some traction but not enough to justify the time cost. The creator can't let go because "I've put so much into it" and "it might take off."
CT10: Calculate the opportunity cost. What else could you do with those 15 hours a week? If the alternative use of that time produces higher returns — in money, learning, health, relationships — the venture is a negative-ROI allocation that's being subsidized by emotional attachment. "It might take off" is not a thesis. It's a hope. After a year of data, you have enough signal to evaluate the trajectory. If the trajectory doesn't support the continued investment, the time is worth more elsewhere.
This is not a failure. It's a reallocation. The year of work produced information: this specific approach, with this audience, at this scale, doesn't convert at the rate required to justify the investment. That's valuable data. Use it to make a better allocation. Don't use it as a reason to continue a bad one.