kooboy blog

How to Start a Startup / Startup School by Y Combinator

February 12, 2020

Lecture note for Startup SChool Ch. 1


  1. You should only start a startup because you find there is a problem.
  2. Also you believe starting a company is the best way to solve it
  3. The passion comes first, starting a company is second

4 elements of startup

  1. Idea
  2. Product
  3. Team
  4. Execution

1. Idea

  • People say ideas are not worth it, but it’s not true.
  • “Ideas did not matter much” - not totally wrong, but not right.
  • Best companies are mission oriented.

    • The company should feel like an important mission
  • Good Startup usually takes 10 years
  • Small market monopoly, and expand fast
  • It is not dangerous to talk about your idea

Idean should sound crazy, but it should be right

  • why now?

    • why this is perfect time for this particular product
    • Talk to your Customers a lot While you are a student
  • Think about ideas
  • Meet your Co-Founders

2. Product

Great Idea -> Great Product -> Great Company

  • Build something small number of people love a lot

    • Intensity of like
    • once people love, you can expand very rapidly
    • You get growth by word of mouth
  • Great Products Win

    • Make something users love
  • Simple is good

    • if forces users to do one thing at a time
  • Fanatical

    • don’t do ads in the very beginning phase
    • Instead, find your team
  • Listen to your users, stay close to them, understand users very well

Product Development Cycle

  1. show it to users
  2. user feedbacks

    1. what do the like
    2. what would they pay for
    3. what woulrd make them recommend it
  3. product decisions

Metrics: Focust on growth

  • Total registrations
  • Active Users
  • Activity Levels
  • Cohort Retentions
  • Revenue
  • Net Promoter Score

Starting a company

  • you need to be able to manage your psycology
People have this vision of being the CEO of a company
they started and being on top of the pyramid...
Waht it's really like: everyone else is your boss - all of
your employees, customers, partners, users, media are your boss.
I've never had more bossess and needed to account for more people today.
The life of most CEOs is reporting to everyone else...if you want to
exercise power and authority over people, join the military or go into politics. Don't be an entrepreneur.
- Phill Libin, CEO of Evernote

3. Team

People(Students) are not so serious about picking up their co-founders. It’s really bad picking random co-founders. So finding a co-founder is either way

  1. Go to college and know your friends
  2. Go work at a compnay and know your colleauge

Try not to hire

  • lots of employees -> higher burn rate
  • SW people should do SW business, medias do medias
  • cost of getting early hire is a lot
  • Before hiring a single person …
  • exreme high bar on hiring

Get the best people

  • Recruiting is hard
  • How much time on hiring as a CEO?

    • Zero or
    • 25% (it’s huge amount of time)

Mediocre engineers do not build great companies

  1. Are they smart?
  2. Do they get things done?
  3. Do I want to spend a lot of time around them?
  4. Good communication skills
  5. Manically determined
  6. Pass the animal test
  7. Would feel comfortable reporting to them


Usually founders are stingy about giving the equity to their first 10 members. Rather they are too generous to give out to investors. Total Backward. Founders should give 10% equity to their first 10 employees with vesting.

You’ve hired the best - now keep them around

Aagain, equity granting is important.

Fire fast

  • worst thing in the company
  • it’s better for the company and it’s better for the employee

4. Execution

  • TBD

and motivation

Johnny Ilmo Koo

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