You do not learn entrepreneurship from books. You learn it by paying tuition, except instead of a few thousand francs a semester, the bills come in the form of wasted months and burned savings. Here are the seven most expensive mistakes first-time founders repeat. Skipping even two of them puts you ahead of most.

1. Building before validating

The classic mistake.

Six months of coding, zero conversations with potential customers, then a quiet launch to crickets.

CB Insights data consistently shows that no-market-need is the leading root cause of failure.

Talk to 20 customers before you write 20 lines of code.

2. Hiring too early

A team feels like progress.

It is not.

Every hire adds salary, management overhead, and pressure to scale before you should.

Stay lean until you have repeatable revenue.

The best early-stage teams are uncomfortably small.

3. Picking the wrong co-founder

Harvard Business School research by Noam Wasserman, drawing on data from 10,000 founders, found that 65% of startup failures trace back to people problems rather than product or market issues.

Most co-founder breakups are predictable from week one:

• Unclear roles

• Mismatched ambition

• No honest conversation about money or exits

Spend three months working on a paid project together before signing anything.

Lawyers can fix paperwork; they cannot fix bad chemistry.

4. Raising money you do not need

VC money looks like fuel.

It is also a clock.

The moment you raise, you have committed to growing fast enough to justify the next round.

Many founders would build healthier businesses if they did not raise, or raised half what they raised.

Money solves some problems and creates new, sharper ones.

5. Mistaking activity for progress

Logos, pitch decks, podcast appearances, Slack groups, branding workshops.

None of it matters if nobody is paying.

The only two questions that count in year one:

• Are people using it?

• Are they paying?

Everything else is theatre.

6. Ignoring distribution

Founders fall in love with the product and treat marketing as an afterthought.

Then they wonder why a worse competitor is winning.

A mediocre product with great distribution beats a great product with no distribution, almost every time.

Plan how customers will find you before you finish building what they will find.

7. Refusing to kill bad ideas

Sunk cost is the founder's silent killer.

You will know an idea is dead months before you admit it.

The faster you can say:

"This is not working, let us try something else,"

the longer your runway and the higher your odds.

Bottom line

Avoid these seven and you have already outperformed 80% of first-time founders.

Make them anyway and learn faster than the next person.