If they do they won't reply to those questions. I have friends that are terrible rich by earning it and the first thing they learn is that life is better when few people know about it. (Thieves, kidnappers and envious get out of your life). They life normal lives.
Those that inherit, well, that is another story.
The most common pattern I see is doing a startup, failing, but learning enough about how to do it right, and then trying again and having moderate success with #2 or #3.
9/10 of startups failing could be explained by "virtually all first-time startups fail, and 9/10 founders give up after their first failure, and those that stick with it, succeed". That would actually be rather encouraging.
Almost nobody I know working for a big company is working for their first big company, so you could also say "9/10 of all employments fail", but that's hardly an indictment of employment.
There are exceptions to that rule and ways to increase the odds. As an example, 90% of franchise businesses are still running after 5 years.
Some businesses are only meant to last a couple of years. Lots of owners start several businesses and eventually focus on one. Most numbers you hear are based on the number of businesses registered & renewed/not renewed, a terrible way of measuring both these things.
Though I would argue that as the owner of two retail locations, I am probably better equipped to make that judgement than most.
In my experience, most retail leases are for 5 year terms. I can't imagine that the default rate on those is anywhere near 50%. Most business "failures" likely never got far enough to sign a lease.