What is the secret? ;)
1: build a great product for a very large market, by very large I mean mums and dads can use the product.
For example, if you build a startup say a CRM for Lawyers, think how big can it get. Take uber, they have a very large market because mums and dads (all of us) can use the product.
2: marketing, marketing and more marketing. It creates hype..