Million’s doing site flipping?

Hey guys just wondering I seen tons of people here flipping 2-4 website per month for living,HOW????
Like how you build and sale a website under a month?
I don't think it's possible to make big $ with a site only few days old,what's the catch?
The secret and how I can flip 2-3 websites per Month too?
Should I buy improve and sell or build from scratch(I don't think it's possible)?
Please really curious to learn!

HELP A NOOB OR A PUPPY WILL GET EATEN IN CHINA:p