The Feature That Wouldn't Die: Escaping the Sunk Cost Fallacy

The Concorde jet was a technological marvel, crossing the Atlantic in three hours, but it was a financial disaster from day one. Despite billions in cost overruns and obvious data showing it would never be profitable, the French and British governments refused to pull the plug, pouring money into it for another decade simply to justify what they had already spent.

This irrational behavior is so famous it birthed the "Concorde Fallacy"—building a beautiful, doomed machine because you are too afraid to admit that the early investment is gone.

In B2B SaaS, we build Concordes every day. We poll "Zombie Features" until they shine, refusing to kill them because "we've already spent six months on it." This is the Sunk Cost Fallacy: throwing good money after bad to avoid the psychological pain of a loss, while the market indifferently moves on.

Where are the Concordes in your backlog?

In B2B tech, sunk costs hide in our product roadmaps, our tech stacks, and our marketing channels.

The psychological driver here is "loss aversion." We feel the pain of a loss twice as intensely as the pleasure of a gain. Admitting that the last six months of dev time were "wasted" feels like a physical blow. So we construct a narrative to protect our egos. We say things like, "We are pivoting the scope," or "It's an investment in the platform."

But the market doesn't care about your ego, and it definitely doesn't care about your sunk costs.

The Zombie Feature

This is the feature that looked great on a whiteboard but proved useless in beta. Instead of killing it, we keep iterating. "Maybe if we add a dark mode?" "Maybe if we change the button color?" We polish a turd until it gleams, burning resources that could have built something valuable.

The Legacy Enterprise Deal

Your sales rep has been working on "Big Corp Inc" for 14 months. They have flown out for three demos. They have rewritten the proposal five times. The prospect has gone silent. But the rep won't move the deal to "Closed Lost" because "I've put too much into this." Meanwhile, five closeable mid-market deals are being ignored. The time spent is gone; spending more time won't bring it back.

The "Strategic" Partnership

You signed a partnership with a legacy vendor. The integration was a nightmare. The co-marketing yielded zero leads. But you keep the logo on your homepage and keep renewing the contract because "undoing the integration would be a hassle."

How do you cut the cord?

Focus on Future Value, Not Past Cost: A rational decision maker asks only one question: "Given where we are today, is this the best use of our next dollar/hour?" If the answer is no, stop. The past money is gone. You are not "saving" it by spending more.

Reframe "Quitting" as "Harvesting Data": If you kill a project, you didn't waste six months. You bought six months of education on what doesn't work. That is a valid asset, but only if you actually stop and learn from it.

Create "Kill Criteria" Upfront: Before starting a project, define the failure state. "If we don't have 10 beta users by March 1st, we kill this." When the decision is made by Past You (who was unemotional and rational), it's easier for Present You (who is tired and invested) to pull the plug.

The bravest thing a product leader can do is look at a roadmap item that is 90% done and delete it because it no longer serves the customer. Don't build a Concorde.