1. You can discover the counterparty using their registered mobile phone number tied with their bank account. In B2B and P2P scenarios, the business or the individual already has the counterparty's phone number in most cases. So, this handles like 90% of the cases of simple discoverability. For use cases like sending money to friends/family, this is perfect.

2. The mapping of the virtual address to the bank account is maintained and managed by the banks (as part of the bank's UPI interface mandated by the standard) and shared with the NPCI's UPI backend using tokenization.

3. A user can create multiple virtual private addresses [VPAs] (eg: mybillpay@bigbank, subscriptions@bigbank etc.,). The user can then track their spends/receipts by VPA.

The ease of use is an order of magnitude higher compared to entering bank account information. Settlements are bank-to-bank and instantaneous (~2-3 secs) powered by the NPCI backbone.

India used to have a high use of Cash-on-delivery (COD) for e-commerce. This gave a good electronic equivalent for COD that also helped e-com operators.

I see how that makes sense for most people, but I have so many emails and phone numbers and change them so frequently that I find it somewhat spooky. Providers can re-assign a phone number after some time, and when I transfer money using a phone number the app does not show me the name of the recipient before making the transfer (understandably, as that would be a terrible privacy leak), so I don't feel comfortable doing it...

At the same time, I am pretty sure that banks are loth to re-assign an account number, and if they do so, have processes in place that are adequate to the significance of that (as opposed to telco providers, who presumably did not intend for their phone numbers to serve as an identifier for money transfers...)