The full version of the original question: Isn’t trying to build your own rather than building on the backs of giants and leveraging their ecosystems like sailing the Atlantic in an inner tube?
"Building on the backs of giants" sounds attractive, but...
1. We don't go the ERC20 or similar path as many other projects do because this is deadend for real projects in the payment industry. For example, you cannot create most business apps without the ability to create millions of various tokens - several tokens per each business entity or even per each consumer. This feature is not available if you piggyback on someone else’s blockchain.
2. Forking an existing blockchain code is another option - we already did it when just started GRAFT. It turns out that in our case the only choice is to code from scratch and get exactly what we need rather than trying to operate on an open heart and grafting the features that do not belong there: high scalability, no chargebacks, no locked balances, zero fees, instant authorizations and settlements.
3. We are not just building a ledger and business apps. We are building a platform that will be open to third party developers through simple API so they can offer additional apps and services using the same merchant tokens to both merchants and buyers. For example, alternative wallet apps, reporting apps, promotions campaign apps, token marketplace, token exchange, etc. This way we get an opportunity to become a giant.
See also: Why do you develop a new technology instead of reusing the existing one?