One of my instructors used to tell us to stop doing "gokiburi Aikido" when we didn't complete every movement swiftly and sharply at the right place but instead moved our hands around trying to find the right spot to hold to do nikajo or whatever.
For those of you who don't know "gokiburi" is Japanese for cockroach so his analogy of what we were doing with our hands was pretty graphic for me...hands scuttling around like cockroaches trying to find nikajo...yuch.
I now use that analogy with my students (but I always give credit to my instructor for thinking it up...no way I want people to think I came up with that by myself)
--Michael