That's not true in a "seller's" market. When I moved to Palo Alto, in 1971, average houses were on the market for 3 days. I looked at houses, for about a week. Then flew my wife in for the final selection... All the houses I selected were sold before she even got to see them.
I don't recall the exact figures, but according to studies we spend less time in deciding on a home purchase than in making any other major buying decision. Something like a few hours on average. The house we live in now, we saw for the first time on Sunday and were in escrow on Tuesday. If we'd waited any longer we'd have lost it -- and this was not even in a "seller's market."