When capitalism hits these limits, investors find themselves with fewer options for investing their capital, since nothing gives an acceptably high return. They can't just put it into savings because interest rates on savings accounts are typically lower than inflation, and that means losing money. This is what economists call a crisis of over-accumulation. In a crisis of over-accumulation, capital begins to lose its value--and according to the driving logic of capitalism, this cannot be allowed to happen. In order for capitalism to carry on, crises of over-accumulation have to be solved, someone needs to step in to provide a way to mop up the excess capital, to funnel it into some kind of profitable investment. It is an iron law.