Ten years can turn a career into more than a job. It becomes a qualification, a reputation, a network, a salary level and eventually part of the answer to “What do you do?”
Then the path stops fitting.
At that point leaving does not feel like choosing something new. It can feel like declaring the previous decade a mistake.
That is where sunk cost becomes powerful. It is the tendency to let resources already spent influence whether we keep investing even when they cannot be recovered. Research finds the effect is real but varies by situation. Recent work points to mechanisms including loss framing, opportunity costs and self-justification.
None of this means ten years should be discarded casually. Tenure can produce expertise, trust, income and access that would be expensive to rebuild. Experience can create genuine future returns.
The distinction is simpler: is the past an asset for the future or merely an argument against changing it?
Professional identity makes this harder. A 2026 review notes that career transitions can disrupt an established sense of professional self. You are not only asking whether another role would suit you better. You may be asking who you are without the title, field or story that has explained you for years.
Past investment deserves respect. It does not automatically deserve another investment.
This is where Herbert Simon’s idea of satisficing is useful. Real people do not optimise across every possible career because information, attention and time are limited. “Good enough” can be rational. But a path chosen under old constraints should not become permanent simply because reconsidering it is uncomfortable.
Try a harsher test than “Have I come too far to leave?”
Imagine the previous ten years cannot be recovered whether you stay or go. Your degree remains earned. Your experience and reputation remain yours.
From this point forward, knowing what you know now, would you choose another five years of this path?
If yes, staying is not sunk cost. It is a fresh investment.
If no, the decade may already have given you what it had to give.
Past investment deserves respect. It does not automatically deserve another five years.
If you stay because of how far you have come, ask whether you would choose this path again from today.
→ Play The Pressure Room: see how you decide under pressure
