I can totally believe it- it's just that we're repeatedly sold stories about startups that get hockey stick growth two days after launch.
I remember seeing an interview with the founder of Pinterest, who was slightly annoyed at the coverage they'd been getting- they had been working on it since 2008, but everyone was talking about it as if it had just launched.
How many of those hockey-stick startups have actually stuck around? How many of them had their graph of Actual Time In Use fall off as sharply as their initial userbase blew up?