Just luxury spending and underperforming investments. Essential spending can't be deferred, and worthwhile investments will outpace any natural rate of deflation. Forced inflation drives conspicuous consumption and malinvestment, but in doing so it increases monetary velocity, which helps bankers and tax collectors extract higher rent from the economy.

This is something you can think about from a micro economic level! think of your next big dollar purchase. Maybe its a car, or a TV or a computer or a kayak. Whatever it is, you probably have to save up to buy it, you probably spend a lot of time researching and thinking about which one to buy, and you wait for a good time to buy. If you know that simply waiting another few months means you can get it for cheaper, would you? If the answer is yes, then that's how deflation would effect every luxury and other non-necessity purchase