Universal Basic Income (UBI) has one intrinsically good feature: it ends the harmful idea that human worth is tied to a person’s ability to labour and produce profit. Instead it says every person is intrinsically valuable and everyone deserves the necessities to live and take part in society.
After this however the Devil is in the detail. UBI is a tool and tools can either help or harm. Unfortunately too much discussion of UBI neglects the essential details that determine if the versions of UBI being proposed is harmful or helpful. So here briefly are the necessary features of UBI that are required for it not to harm people:
One question to ask yourself is: Would I be content to live on the level of UBI I am proposing? Unless the answer is Yes, you are proposing a UBI that is regressive and harmful.
UBI must be set at a level that provides for an income that allows a person to live on it, in dignity and inclusion with society. In the UK the Joseph Rowntree Foundation (JRF) estimate  the minimum income for a single person to live in society is £17K. Currently Job Seekers Allowance (JSA) is £73, this is not enough to live on and anyone proposing this level will be harming people with their UBI ideas. Unemployment benefit has been devalued over the previous 4 decades, if we were to have it at the level of proportion of earnings it was 40 years ago, it would be £140 plus payments for rent and disability on top. So under the subject of level it must also be asked- is UBI to be parallel to existing social security systems, or a replacement? If a replacement if must also feature discussion of how housing is to be provided, regulated, and paid for.
UBI must address ongoing inequality and seek to reduce it over time, this is best achieved by funding it through a progressive and just tax regime. Currently the global consensus is against taxation in general and particularly against a progressive system. In the UK alone there is a tax gap of circa £120Bn  which is not being addressed and the current effect of the overall taxation system has lessened in its progressive effects to being almost flat in that regard . Any UBI proposal that does not address how this situation is solved will be regressive and harmful.
3. Social Justice and Human Rights
UBI must pay additional amounts to people whose everyday living costs are greater than the average, generally this means those with children or caring responsibilities and deaf, chronically sick, and disabled people. Any UBI that does not build in additional support for these groups will be regressive and harmful.
Any discussion of UBI without a discussion of these three features will necessarily be incomplete, and thus regressive and harmful.
Most versions of UBI being proposed or tested fail these three criteria and this failure is not being discussed. This makes the current UBI movement extremely dangerous and more akin to proposing a subsistence subsidy of labour that is to benefit business, and not a system to nurture human and planetary welfare. It would perhaps be better to look at more profound and holistic analyses of our political and social economies and how to turn those from being oppressive into nurturing and just systems that will avoid our extinction as a species. Have a Doughnut ?
UN Special Rapporteur on extreme poverty & human rights Philip Alston’s very good overview of UBI http://ap.ohchr.org/documents/dpage_e.aspx?si=A/HRC/35/26
And a treasury of UBI links: