UBI and welfare (what we have in Australia) are very different. Andrew Yang has spoken about this better than I could off the top of my head, but to add a few things about our system (which does work very well from a global perspective):

* The stigma (in non-covid times) toward "dole bludgers" is pretty significant. We're a pretty egalitarian society, but there's a fairly common distain towards welfare recipients. This would likely be reduced if everyone was receiving the payment.

* You mentioned that recipients receive payments even if they quit or can't be bothered getting a job. That's kind of the situation with the current payment (JobSeeker), which was created last year when covid hit. The usual adult benefit (formally called Newstart allowance) had very strict "mutual obligations" and required you to apply for N number of jobs per fortnight otherwise your benefits were cut (https://www.servicesaustralia.gov.au/individuals/topics/mutu...). Also, if you quit a job you would have a cooldown period (usually 8 weeks) before you would receive benefits (with exceptions for injuries, redundancy, etc).

* Rent assistance is basically guaranteed. If you pay rent, you will get a portion of this covered.

* Our welfare program also includes a pharmaceutical discount (almost all prescription meds are $6.60 for recipients).

It's a really decent program overall, but it's not UBI.