Tatum supports more than 20 blockchains or crypto assets. Every blockchain works differently, each with its own features and functionalities. It is difficult enough for developers to learn one of them, and working with more than one is almost impossible.
Tatum allows developers to utilize direct blockchain API calls almost identical to the native JSON RPC of each blockchain. On top of that, it builds a small abstraction layer across multiple blockchain protocols, so API calls look very similar for different blockchains.
In case you're wondering if developers could instead choose to leverage native blockchain functionalities, the answer is yes, but it would take a long time to finish such a project. There are a lot of features that a standard enterprise-grade application should have. A few examples are:
Notification of every incoming transaction
Automatic synchronization of balances to blockchain addresses
This could be achieved via native blockchain API calls, but it would take a long time and introduce many bugs and mistakes. This is why Tatum has created its own private ledger, which can be connected to any blockchain, with all of the standard enterprise features built-in automatically.