Personally, I'm curious to unpack why "welfare spawns laziness and lack of ambition." What are the assumptions underpinning this claim, and what do you mean by "laziness" and "lack of ambition?"
It has become obvious that when people have something handed to them, they won't bother trying to learn how or work hard to get it themselves. Nature loves competition.
As an example, look at big business when they are the only part of a market. With nothing to compete with, they simply stagnate on innovation.
Most of mankind's greatest advances came through war or technology stemming from war-based innovation.
I think you could certainly have structures that encourage a competitive business environment without having 1/6 kids in the USA wondering where their next meal is coming from, poverty and homelessness at the rates we have them, or minority oppression the way we have them.
As for what happens "when people have something handed to them," and how that relates to those worst-off in society, I think we'll get some more information about that in the next couple years as more places are beginning to experiment with universal basic experiment.
"Nature loves competition" is an assumption about nature - and about human nature - that may or may not be true. Personally, I'm not convinced, and it is at least also true that "nature loves cooperation," and that both innovation and the health of any ecosystem result also from cooperation, symbiotic and synergistic relationships.