Capitalism and the Risks of a Hoard

For every dollar that isn't spent back into production, it forms what marx calls a hoard. This is an amount of money that isn't being used productively to some extent. It can be used to maybe anticipate disturbances in the production process. But then again, there's a lot of risk ciated with that. What if the machine goes up in price? Or what if you aren't actually able to cover the other things that you're hoarding this money in terms of of cost? People aren't buying your products, and then you get screwed over in the end.