That's a sad statistic. Where did that come from?
It's really just a guess. Here's why I think that.
Many years ago, I did a lot of diving in Cozumel, and the first years I went with the operator from the resort where I stayed. I left that operator when I got tired of people asking to go to beginning dive sites because they were just starting out.
Then I started diving with Dive Paradise, the largest operator on the island, with many boats and many divers. they advertised that they matched divers by ability, and I was frequently frustrated by their inability to put together a boatload of experienced divers. One day they worked with me on this, and I sat down in the office and went through their data on all the divers working with them that week. I was the only one with more than 100 dives.
I did a liveaboard in Roatan last fall, and at the end of the week, they celebrated people's milestones. You would expect a liveaboard to have very serious divers, but only about a third had 100 dives or more.
I live in the heartland of America--Colorado. We are annually among the top 3 states in the nation in terms of numbers of divers
per capita, according to DEMA statistics. Only a
tiny percentage of those divers dive locally for fun--I would guess fewer than 1%. The rest dive on vacations every year or every few years. It takes a lot of years like that to get to 100 dives.
ScubaBoard divers who have hundreds or thousands of dives may look askance at divers with 100 dives, but that is really a lot of dives for the average diver. If someone is doing any kind of reasonable dives while getting to 100, I would expect then to be reasonably good by then. Looking back at my own career and glancing at first logbooks, I would honestly say that I was a pretty solid diver well before I hit 100.