A lot of times we buy replacement items but how often do we actually buy an item before it is needed? A printer could be showing some signs of wear and it will soon find itself out at the curb. An air mattress could spring a leak and see a similar fate. Would you need to replace a printer and an air mattress right away? Possibly.
Does that turn a purchase into an emergency purchase? What happens when your purchase becomes an emergency? You may pay top dollar and you might not get the exact item that you want.
A friend's parents evaluated how long items were supposed to last and started shopping / researching before "the emergency" occurred.
Can you live without a printer, an air mattress or even a lamp until you have time to get the best deal? PREPARE before the emergency occurs.