price is e.g. 1k USD/BTC Alice has 1 BTC she wants to sell for $1k Bob has $995 and places an order to buy 1 BTC at $995 Alice could wait around for someone

price is e.g. 1k USD/BTC Alice has 1 BTC she wants to sell for $1k Bob has $995 and places an order to buy 1 BTC at $995 Alice could wait around for someone to make a better offer, or maybe she needs $ for christmas presents NOW and lets it go for $995, at which point the price becomes $995 The listed price is the valuation at which the last transaction occured.