Yeah, the whole idea of ubi is you replace the patchwork of various social programs (and the overhead of each program) with a basic ubi for everyone. It's supposed to be much more efficient and there's no disincentives to self improvement (because you never lose your benefits).
I personally don't actually think it disincentives working very much because people who want to work for more than just the minimum always will and people who really, really don't wanna work find a way to get out of working within the current system. Since my family is full of degenerates, I've seen every trick in the book used. Out of my dad's family (8 kids) only one (1) has meaningfully participated in paid employment.
I know a few people on disability. Since it's their lifeline they are generally stressed to terrified of losing it. So you have both an disincentive to look for work and risk losing benefits. And the stress also negatively effects their mental health as well. Which also makes it difficult to find productive work.
It's the situation caused by the laws and policies in place and their physical and mental heath issues.
I have some sympathy because I got sick in the early 2000's and couldn't work and was just about overwhelmed with just trying to figure out what was wrong medically. Fortunately I had enough savings to see me through without having to worry about being homeless. And enough professional contacts that I was able to land a light duty job once I started recovering. I only needed to work 3-4 hours a day at first.
The public taxpayer ends up paying for their housing, their food stamps, their bus fare, healthcare, etc. As I indicated, it's multi-generational. However, this is because their behavior is degenerate. They spend all day being paranoid of people coming to take what little they have and lack any sort of trust in each other or themselves. Drugs are involved (including pot) across the board, excepting the little kids who are raised around it.
As an aside, my best friend (prescribed adderall) has always been affected by "the curse of the gifted". When lower grade school is easy. After high school, real intellectual competition breaks that paradigm of "if it isn't easy for me, it's too hard" resulting in similar lazy adult behavior...although he does work. He's never been stable and still hovers just over minimum wage and cannot care for his kids. These problems that have similar outcome (like homelessness) which are often conflated.
Depends on the person, and how they avoid working.
I can only speak to my personal observations.
There's the people who never get a job as an adult and so they never move out of mom and dad's house. Mom and/or dad end up supporting them until their deaths. I asked a guy I know whose son is 37, living with him, and doesn't have a job and hasn't had one in decades (and never worked full time) why he allows that sort of arrangement. He said "because I know he's got a safe place to sleep and something to eat."
There's people who have a kid or two and live off child support. In some states having a one night stand that produces a child with someone who has a salary of ~$120,000 is more lucrative than going to college and working the median salary for a college graduate. Even rape victims owe child support. There's two victims here, the person paying and the child(ren) who exist solely as a paycheck.
There's the related "bait and switch spouse," that's when someone, upon marriage (or cohabitation), just quits their job (or gets fired) and unilaterally decides they don't want to get another. This, of course, was their plan from the start. They may make the motions of trying to get a job to make it look like they are trying to work to their spouse, but the goal is to not work. They will ride this out as long as the spouse will put up with it, which can be decades. This is what my dad did, he basically worked for a couple weeks of my parents marriage and my mom has been footing the bill for him in the 4 decades since (and, no, he never took care of the housework or childrearing or anything like that).
Then, finally, we have the fake disability people. Claim you can't work due to pain, depression, anxiety, migraines, etc. Anything that's a subjective diagnosis. Establish a paper trail, then apply for disability. It really helps if you are in one of the above categories while doing this, because you have a history of "not being able to work" for the disability claim.
I personally don't actually think it disincentives working very much because people who want to work for more than just the minimum always will and people who really, really don't wanna work find a way to get out of working within the current system. Since my family is full of degenerates, I've seen every trick in the book used. Out of my dad's family (8 kids) only one (1) has meaningfully participated in paid employment.