So far, universal basic income pilots have shown that people will not suddenly stop working if they have enough money to live, though. We could, in fact, increase the productivity of society by erasing the amount of time wasted for survival in poverty, while still rewarding workers that work harder/smarter or sacrifices more for their efforts.
That would be a much more meritocratic society where everyone has close to the same opportunity, compared to one where too many people struggle with poverty from the time they're born.... while some are spoonfed w/ gold gilded spoon since even before they were born.
The theory of motivation would explain the observation in the basic income pilots, that there are many forms of motivation and that survival need not be the only source of motivation we care about. The idea that we need to rely on survival as the primary motivation for production, should be left to the ancient primitive societies where resources were so scarce.
The very root source of all motivation is really the pursuit of happiness and the avoidance of suffering. Stagnation is suffering, which means people will have the motivation to do things to get out of stagnation. Earning more money to build a better life, creating things, making others happy, contributing to society tends to be a source of happiness, no matter how much money that one has, which would also be healthy sources of motivation. That's partly due to the fact that whenever people have more, the new situation will become the 'norm' that they could use to compare their future circumstances/goals to. People tend to want more from their life, and they would be better able to do that when we empower them with the basic resources they need to survive.
Living in poverty is a full-time job, and it is a waste of manpower/labor hours. Give people in poverty their cheap basic necessities, out of our abundance of resources, and aid them so that they can find a better job that contributes more to society. Everyone else would be better off, crime will drop, everyone would be better educated, productivity would increase, the economy would thrive, innovation will flourish, and so on.
Right now, anti-welfare people would rather keep people homeless even if it cost 3 times as much than housing them. These people, instead, have to waste time surviving being homeless.... while taxpayers waste 3 times as much money being ideological extremists rather than being helpful.
Fiscal responsibility supports the right kind of welfare. One aspect of the right kind of welfare is about ensuring that everyone that could be productive is capable of being productive and that they not forced to waste their time on unproductive things all due to the stress of needing to survive. It is even better when doing so is actually so much cheaper than the cost of leaving people to suffer.