I Calculated My Biggest Money Mistake. It Cost €100k.
Between 2010 and 2020, I made quiet mistakes. Not dramatic ones. Just habits repeated long enough that the damage ran close to €100,000.

What you'll learn
- Why quiet habits can be expensive
- How opportunity cost hides inside decisions
- Why repeated behavior matters
I Calculated My Biggest Money Mistake. It Cost €100k.
The expensive mistakes were quiet
Financial damage can come from decisions that look harmless one at a time.
Ten years changes the scale
A small amount repeated for a decade is no longer small.
Opportunity cost is invisible
Money spent or left idle also has a second cost: what it could have built.
The number made it real
Calculating the cumulative effect changes how you see the pattern.
Fix the system, not the guilt
The useful response is changing the system that produced the mistake.
The Money Mistake I Kept Repeating
The deeper Mike Petry Journal essay connected to Episode 13, exploring the idea behind the episode from the perspective of money, behaviour and financial freedom.
Read the essay on Mike Petry Journal →What is Episode 13 about?
Between 2010 and 2020, I made quiet mistakes. Not dramatic ones. Just habits repeated long enough that the damage ran close to €100,000.
Why quiet habits can be expensive
Financial damage can come from decisions that look harmless one at a time.
How opportunity cost hides inside decisions
A small amount repeated for a decade is no longer small.
Educational and entertainment content only. This page is not financial advice. Do your own research or speak with a qualified professional before making financial decisions.