There are two issues being confused here.
First, a freelance anything may work intermittently, or may have a backlog of demand and work steadily. This is a function of market demand.
The second matter is how often a freelance journalist/musician/graphic artist may choose to work. This is the supply side of the market equation.
I suggest you ignore the second point, and focus on the intermittent nature of the work.
Cases:
1. Unlimited supply by freelancer, limited market demand. Work is intermittent.
2. Limited supply by freelancer, overwhelming market demand. Work is intermittent.
3. Unlimited supply by freelancer, overwhelming or steady market demand. Work is steady.
4. Limited supply by freelancer, overwhelming or steady market demand. Work is intermittent.