I genuinely admire Morgan Housel. I think he is a brilliant and talented writer. However, he sent out a tweet on Friday that really struck a chord with me.

If you’re less than 50 years old and the market returns at least 5% a year on average the Dow will hit 100,000 in most of your lifetimes. Less than age 30, it’ll hit 500,000 for most of you. Enjoy the weekend.

— Morgan Housel (@morganhousel) October 20, 2017

It’s an innocuous tweet, meant with the best of intentions to leave you with a sense of optimism as you headed into your weekend. 

I get it. Really.

As Bob Farrell once quipped:

“Bull markets are more fun than bear markets.” 

Bull markets also “sell” financial products, services, and offerings. Wall Street makes money selling products and services to “Main Street” who makes money with higher prices. Financial media makes money as advertisers market their “wares.” Being bullish also gets views, likes, comments, and shares. Bull markets thrive when “greed” erases the memories of previous “bear market”losses.

As Gordon Gecko said:

“Greed is good.” 

The problem with being “bullish all the time” is that it is also very dangerous.

This is particularly the case in late-stage “bull markets,” where poor investment decisions, and excessive portfolio “risk,” are masked by seemingly ever-rising prices. Previously bad investment ideas, products, and strategies tend to resurface in a different form or package. Investment strategies like 
“buy and hold” and “dollar cost averaging”
 become popular even though they are absolutely guaranteed to leave you well short of your financial objectives in the future.

So, what does this have to do with Morgan’s tweet?