Indeed mass psychology is something that quite heavily dictates stock markets. Expectations, crumbled dreams of an easy buck and sheep mentality. Funny watching people at work... Last month they went on and on about their stock investments and bitcoin or whatever cookiecutter shit they jump on at just the peak and wrong time like the greater sheepish mass always do. And now the last week they have this bitter/serious tone in their voice when the subject was brought up. 
Human nature never changes. I've dealt with the same thing many times.
I lived in San Diego during the RE boom and crash. I told people a crash was coming, they laughed at me. Then 2006/07 came. Oooops.
I had a few people at a 2017 Chirstmas party tell me the stock market will never crash. lol
I told people on here blipcoin was a Ponzi bubble mania, they laughed, told me I was jealous, and I
"didn't understand it" and
"it's a new revolution" and the most ridiculous one,
"blipcoin will hit $1 million" lol
I have bliptards on here telling me gold is worthless.

It goes on and on.
Successful investing is all about timing and being able to identify undervalued assets. Buy low, wait, then sell high. I've done it consistently, over and over again.