One day when I was very frustrated with a whole lot of problems that were all feeding off each other, the Crow-Rat-Lizard-Mite principle came to me and made things clear.
Imagine you have a beautiful but delicate carpet that for some reason has gotten infested with mites in an area. You don’t want to bleach or do anything there that could ruin the carpet itself, but you do have to get the mites out immediately.
In comes a lizard and carefully picks out the mites. But lizard grows fat and happy and decides to live there.