A transaction is comprised of one or more transfers between different entities. A single transaction may contain dozens of distinct transfers, which represent the movements of native units from one ledger entity to another distinct ledger entity. Only transfers that have a positive (non-zero) value are counted. Transfers have been colloquially referred to as "payments".
For ETH, we do not count failed transactions or self-sends towards TxTfrCnt. We do count internal transfers and do not distinguish them from top-level transfers. One way to think of TxTfrCnt is to count each time ETH effectively changes hands (excluding payment of fees and new issuance)
Consider a single Bitcoin transaction that represents a company's payroll. The company broadcasting this transaction spends one input and generates 12 UTXOs, one for each of its employees. In this example, that transaction would entail 12 transfers.