Don't kid yourself that secrecy was not the main driver for foreigners holding accounts in Switzerland. Those entities became good at what they do because for a

Don't kid yourself that secrecy was not the main driver for foreigners holding accounts in Switzerland. Those entities became good at what they do because for a long time they were the main option for people wanting to hide money (legitimate or illegitimate) and with that came the funding to hire people who were good at it.