While certainly a popular sentiment, it's not entirely accurate. There are little fires here and little fires there, and it's true that houses in some areas are selling faster than others and some types of houses generate multiple offers.
In order to understand the market we are currently in, you need to understand what is driving the multiple offers, low inventory, etc.
A metric that REALTORS® use is the "Sales to List Price Ratio", or in others words... What is the percentage of price over the list price that homes are selling for?... On average!
Currently it is at 103.99%* which means that if a house was listed at $100,000 it would, on average, sell for $103,990. If it was listed at $300,000 it would, on average, sell for $311,970.