Just the idea of the supplementing it requires. It's phased in with earnings. That could be employment income or it could be self-employment income. The idea is to support low-income families in a way that's connected to work. That requires you to have a job. That's the encouragement. As I mentioned, phasing it out more gradually means people who are in the income range where it's being phased out will lose a little less of their benefit as their income goes up.
On April 24th, 2018. See this statement in context.