The best way to go broke - misidentify "10% success" companies as "50% success" companies. Obviously no one, including you or me, can precisely determine the odds of any given company succeeding. But speculators know they get far more losers than winners, and expect the big gains of the winners to more than compensate for the numerous losses. Successful investors wait until they have much more certainty, and have fewer losers, but have far fewer 10 baggers too. Most of the big money in the market consists of investors, but there are some real and successful speculators out there. Whether you consider yourself to be an investor or a speculator, the reality is that if you own Nanoviricides stock you are speculating. Don't mistake it for an investment.
Most small businesses fail. So by your reasoning no one would ever invest in any of them. But people keep doing so.