Because eventually time catches up with everyone and you have to start living and stop waiting?
Of course for people who don’t buy into the “a person’s house is their castle” way of thinking and have no psychological need/desire to own the best home they’ll ever own in their lives (before they’re too old to enjoy it) or raise kids in said home and send them to the school of choice, this means nothing to them and will not be concerned.
For many of us, I suspect, life goes on and at some point you need to get on with it and plant your roots. And waiting for the ideal timing of the market is a false economy where the money you might save is not worth the time lost.