There is also land and capital, of course, but it is not very often that the landlords don't also want a raise when labor starts making more money. That is their living, after all. For all intents and purposes there is only labor.

Granted, you can often play political games with labor, such as only raising the wages of workers in the USA, while leaving the labor making the plastic trinkets in who knows what third-world country to continue to struggle. In that sense, it doesn't necessarily happen linearly. Not really achieving the goal of a "living" wage then, though.