Full Idea
A regress is vicious if the problem at level n can only be solved at level n+1; it is non-vicious if it can be solved at n, but the solution forces another level n+1, where the problem can be reformulated.
Gist of Idea
Vicious regresses force you to another level; non-vicious imply another level
Source
Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 2.3.2)
Book Reference
Baron,S/Miller,K: 'Introduction to the Philosophy of Time' [Polity 2019], p.46
A Reaction
So in a vicious regress you chase the apparent solution, but never attain it. In the non-vicious you solve it, but then find you have a new problem. I think.