Only a very small percentage of people are highly self motivated without the need for outside motivation or incentive to spur them to work very hard to achieve. The overwhelming vast majoriy work based on incentive or disincentive. You will get X if you do this, or you will be punished X if you do not do this. Once you take this motivation to work away, by giving a guaranteed income, the productivity of your nation falls to the floor. This is why all socialist states in history have failed. The cost is way too high to be supported by the production of a poorly productive populace. It's not rocket science, but politicians will always seek the "I will give you free stuff" vote.