However, what I generally understand is happening, or rather is not happening, is called "pushing on a string". No matter how low the rates or availability of loans (not so sure that was true in Japan in the '90s), nothing can get a business to borrow money if they don't think they'll be able to pay it back.
I'd also suspect that's somewhere in the priority list of central banks below preventing widespread bank failures (note what happened after it was decided to throw Lehman Brothers to the dogs, albeit we'd better be past that point in the US), and very possibly making it very cheap for the government to borrow money. "Trillion dollar deficits as far as the eye can see" don't hurt so much when interest rates are so low....