Yes, it's totally up to the individual. I like this challenge, as it also challenged me to rethink why I wanted to join this challenge in the first place. So I'm also still continuing and making myself write a poem every day. And I'm very glad I have allowed myself to not feel forced to follow any other rules for it, or to have to 'produce' something publishable within a day. Or even two days.
Any limitation on creativity kills most of it. Or kills the part I like to evoke through this challenge...
Best of luck to you!