Same as any crash: If people think the market is going to do worse than a bank account in the near term, they sell. If enough people agree, it's a self-fulfilling prophecy.
Market Crashes are not that simple. More often than not they are a form of liquidity crisis on debt instruments that are poorly designed and lack the advertised returns after long term investment. Typically these bonds have low security collateral and high risk. In 2008 this was related to the subprime mortgage bubble, the coming bubble is sometimes referred to as the everything bubble. This will probably be escalated by the Trump Tax Cuts as many in the middle class ended up paying more in the last year than in previous years due to punitive removal of certain deductions designed to punish blue states.
> as many in the middle class ended up paying more in the last year than in previous years due to punitive removal of certain deductions designed to punish blue states.
I believe that the cap on deductions was a deliberate attack on blue states; I also believe a lot of people who received a tax cut believe that their taxes had risen.
Most of my co-workers who own a home paid additional taxes than we did last year. For a politically motivated myth it sure looks like $1.5k more than paid last year.
