It should really be unconditional basic income (as it's called sometimes). The main risk I see is that conditions creep in, e.g. if it gets tested only on people who are currently on welfare. I think a low UBI can still have a small effect, and there is no need to go from zero to 1000€ per month in a single day. The amount can be adjusted by the usual political processes, and if it gets adjusted towards zero, well - then maybe the people who vote didn't actually want to grant this small amount of freedom to each other.