I interviewed 5 billionaires this week

I asked them to share their lessons learned on startups, life and entrepreneurship:

Here's what they told me:

A startup idea isn't "one" idea

It's a 10000 ideas, 100,000 decisions and 1,000,000 headaches

You will lose some friends. Kiss most of your high school friends goodbye

Certainties of life:

- Death
- Taxes
- Losing friends

A sign of wealth:

No longer needing an alarm clock to wake up

When in doubt, please don't send that angry email response

Wait 24h. Go for a walk

Angriness makes you drunk. Send emails sobers

Career advice:

Quit your job if it makes you exhausted (if you can)

Be grateful for your job if it fills you up with energy

Likable people win

People sense those good vibes. It does wonders for your startup, career or life

You will doubt yourself a million times

It's only natural

Constantly cut your losses

Harmful in the short term, lucrative in the long run

A sign of wealth: no envy, no fear

You can't build great products without being "at one" with the niche you're building it for

It's almost impossible

Deeply understand your niche or expect disappointments

Enjoy the process

Building a startup should never feel like a grind

Building a startup is a privilege

A satisfying life doesn't require much

Wonderful health, enjoyable work & a caring family & friends.

Success is inevitable.