The welfare system creates perverse incentives, so let's put the entire country on welfare, by way of even more perverse incentives! Brilliant!
This is entirely incorrect. The entire point of unifying welfare into UBI is making it so there's
one perverse incentive in the form of that minimum living standard, instead of the suite of rewarded and often detrimental behaviors like single motherhood. The two solutions for that I generally lean toward are having it as an unemployment benefit package and consequently
on a time limit, and structuring it as making up for wages that corporations aren't up to paying to substitute for a hard minimum wage.
The latter means that low-margin, low liquidity business like local retail that flat-out don't have the money to spare for properly livable wages are still perfectly acceptable jobs, as the business isn't
forced into spending money it doesn't have while the workers are still given proper income for the job, but the larger companies have a mix of PR and tax incentives to actually pay that out of pocket. Delay the government's share by a week, for example.
Because it's an incentive structure and welfare program instead of a minimum wage law, it can't be used to fuck up the economy anywhere near as badly, because if they raise it, the businesses that can't afford it just refuse and the money then comes out of the government coffers. This also means that starting up a business becomes easier because manpower is initially
far cheaper, because you can lean on the government for wages to hold onto liquid assets for initial expansion to profitability.
The degenerate condition of that method of UBI can be dealt with by additionally having it be a proportion up to a certain total, so that, say, half of the "minimum" wage comes from the company and half from the government making lower amounts actually lower the pay, then the company paying a larger share translates to tax breaks on a dollars-per-dollar basis so it's a net gain in yearly profits to pay that full sum out of pocket. The more the taxes rise, the stronger an incentive it becomes.