[Retric]

Volatility can be highly valuable in the long term to keep markets honest. Without that there is a tendency to add leverage until something far more significant breaks down.

[mannykannot]

It doesn't work that way if you make significant bonuses on the wins and the client takes the losses.

[smallnamespace]

Generally not this sort of volatility though: https://en.wikipedia.org/wiki/2010_Flash_Crash

[Retric]

The S&P 500 erased all losses within a week, but selling soon took over again and the indices reached lower depths within two weeks.

So, arguably the rebound is what was odd not the dip. There is a bias when looking at stock markets that says up is good and down is bad. However, accuracy is vastly i more important for the overall economy.