The #1 Cognitive Bias Killing Your Startup
Why past investment is costing you your future
👋 Merhaba, I’m Burak. Each week, I share lessons from 26+ years of building, investing in, and mentoring startups across emerging markets, from the early internet days to today’s AI revolution. 🧿
Every founder I know has a feature they won't kill.
It took six months to build. The team pulled weekends. The designer made it beautiful. And nobody uses it.
But they won't remove it.
“We’ve invested too much.”
This is the sunk cost fallacy — and it's the silent killer of startups.
🧠 The Science Behind the Trap
Daniel Kahneman proved that losses feel twice as painful as equivalent gains. So when you've spent 6 months building something, killing it feels like losing 6 months. But keeping it costs you something worse: the next 6 months you'll spend maintaining, explaining, and defending a feature that adds zero value.
🔄 The Pattern I See Everywhere
Founders who won't pivot because “we’ve already raised on this idea.”
Teams that won't fire a toxic early employee because “they were here from day one.”
Companies that won't shut down a product line because “we already built the infrastructure.”
💡 The Antidote
The sunk cost isn't the mistake. Refusing to walk away from it — that's the mistake.
If you wouldn't start it today knowing what you know now, stop it today.
Not next quarter. Not after “one more experiment.” Today.
The best founders I've backed share one trait: they kill their darlings fast. They treat past investment as tuition, not obligation.
Your time is your most expensive resource. Stop spending it on things that only exist because they already exist.
Constantly upgrade your thinking 🤓