Exactly how is it a plus? The goal isn't to make a nominal "unemployment" statistic go down; it's to create valuable things. Your comment makes me think "a receding tide lifts all boats".
People will create what they want to create. For some people growing a nice garden and working on cool stuff around their cheap house will mean more than creating something "more valuable" to society at large. Creation of value or productivity should not be the standard we measure societies by, but instead equity and happiness.
The market doesn't capture and represent all value created by labor. When I call a tow truck to jump start my car, that transaction is captured by the market, but when I call my friend with cables to do the same thing, it is not represented in the GDP. The same thing goes for a lot of "work" that is not done for compensation but adds a great deal of value to community. Basic income recognizes this fact that merely existing as part of a community you are providing some basic value even if you're not paid for that work. I think the critics are right that there are potential cultural problems around entitlement and an unwillingness to contribute in any form, but I'm more optimistic about human nature.
