$1000 a month creates an environment where the poor finance each other: if you lend $100 to your buddy, you have some confidence he can repay the amount, becaus

$1000 a month creates an environment where the poor finance each other: if you lend $100 to your buddy, you have some confidence he can repay the amount, because he is getting something, so emergency debts can be spread out. At $0 a month there is no trust to build, no credible source of income. Nobody has anything, so nobody gets anything, so nothing happens, no opportunity to build a richer economic web is created or pursued. The poor are then in a position where staying idle seems best. What's actually in place today in the US is effectively somewhere in between $0 and $1000, in that you get something if you fill out the right forms regularly and aren't denied one day, and many parts of it are a targeted package with limited liquidity(like EBT). These packages in their current form accomplish exactly the thing you describe of UBI: They create a homeless-industrial complex that allows bleeding hearts to proclaim virtue. Barely keeping people alive doesn't get them to the next rung of the economic ladder, it enmeshes them in a one-way dependency not shared throughout the society. "Universal" is a really important component in effective socialized policies.