Success absolutely does not tend to beget success. There are radically more examples of success not begetting success, than the other way around (and that always has to be true numerically). There's nothing about past success that favors future success, and I'd argue it's the opposite: success today makes it even harder to maintain it tomorrow, as the market will assault your profit centers relentlessly with competition.
Just ask AOL.
Or ask Yahoo.
Or talk to HP about Compaq. Or ask Gateway how their success beget success.
Or talk to HTC about how their early Android success beget even more success.
Or ask Borders and Blockbuster.
Or AltaVista and Lycos and Excite.
Or travel back in time to 1992, and ask IBM how all their success delivered them a massive wave of red ink.
Or Netscape.
Or ask Sun what happened to their incredible sales momentum circa 1999.
The list is extraordinarily long in tech alone.