Only the ones that never make anywhere near to a profit.

I would qualify that as a situation that repeats itself.

If money from new investors is repeatedly used to pay old investors, it resembles a ponzi scheme.

only if the IPO price is completely unrelated to the fundamentals, like it is for Lyft currently.

If it is unrelated to the fundamentals, you are in full speculation territory and the only goal buying the stock is to sell it eventually to a bigger fool that will pay more for it.