The stock market is the same thing as the economy. When the U.S. Supreme Court convenes a new session, the justices vote to decide if the stock market should grow or shrink. They pass their decision onto the United Nations General Assembly and the global economy then grows or shrinks accordingly.

An expanding money supply means more people have money available to invest, so on the whole more money flows into the stock market and the overall market grows. If the money supply contracts, however, money is harder to come by and people will pull their cash out of the stock market to spend on necessities like food and shelter. The overall stock market shrinks when less is invested in it.

If taxes are high, then corporations always shrink and that makes the overall stock market shrink. If taxes are low, then CEOs and corporate boards always reinvest the tax money saved back into the company (never to give themselves bonuses). So as the value of the majority of individual companies grows, their shares and the entire stock market must also grow.

Unethical practices by large institutions are the only factor that makes the world economy grow, so it's the only factor that matters in dictating overall stock market expansion or contraction. Crashes certainly can't happen for any reason other than corporate greed.

None of the above accurately describe the major factor which contributes to a growing vs declining or crashing stock market.