> I never told them what my business does or what I'd use the money for.

This stuck out to me. I'm in the process of opening a bank account in Singapore for a newly registered company, and boy is it difficult.

Hour-long KYC interview. Details of what the business does. Anything remotely controversial could be a red flag. They want to hear about boring B2B services. They want to see evidence of customer communications or contracts, so they can see you're a legit business and not a shell company. This is very difficult for a company that hasn't started operating yet. Why would I start operating without banking? How can I show business activity before commencing operating?

By comparison, I've opened business accounts in both AU and the US without hassle.

It's likely because of the nature of the country. Singapore and the UAE (another similar country) are notoriously difficult for getting started with business banking because banks often expect you to be either well-funded (from elsewhere) or matured as a business. For a long time, they haven't ever evolved their thought to expect startups to natively grow, and even of late, they expect startups to be these well-capitalized entities with angel/VC funding. That, I presume, is because of the fact that these countries tend to be conduits for money rather than destinations themselves - they'll roll out the red carpet for you if you went with another, more "matured" objective in mind like laundering money or expanding into the country.

On the other hand, Switzerland has been surprisingly very easy to get started with quickly, even though Switzerland falls in the same category. You can easily obtain a (shitty service) Postfinance account to get started, and UBS is a breeze to work with, despite being bulge-bracket - even for new companies. Or you can also opt for a cheaper Kantonalbank, which are surprisingly very open to new businesses.

Also international accounts have more stringent KYC of course.

Are you Singaporean? I found opening my business account (UOB) extremely straightforward.