Must be universal and below minimum wage
Dave Timoney 15, British economist, comment on “The Left's Ideas,” Stumbling and Mumbling, 1/30/15, https://stumblingandmumbling.typepad.com/stumbling_and_mumbling/2015/01/the-lefts-ideas.html?cid=6a00d83451cbef69e201b8d0cb802e970c#comment-6a00d83451cbef69e201b8d0cb802e970c
A jobs guarantee wouldn't be paid at the national minimum wage, but slightly below it. This is to encourage labour to move from the public sector to the private sector once the economy picks up and (low-paying) vacancies are created in the latter.
The job guarantee is meant to be a self-regulating mechanism to deal with temporary unemployment. If paid at the NMW (let alone the living wage), this would encourage some workers to prefer the security of a public sector role. For the same reason, the jobs are likely to be unattractive, to avoid workers discounting their wage expectations for pro-social roles.
In practice, job guarantee schemes either tend towards the antiquated model of the 20th century (a labour battalion with the prospect of parole), or they are pro-capital schemes that provide subsidies to business for certain types of worker (e.g. the young or long-term unemployed) for fixed periods. The use of the term "job guarantee" for the latter is questionable - "subsidy guarantee" would be more accurate.