Financial advisors will tell you that you need to have diversification in your investments. Good ones will, anyway.
The idea is that a mix of stocks, bonds, real estate, cash and gold will minimize risk while giving you a decent return.
Life is the same way. A wide mix of activities makes for a richer life. In other words, don't put all of your eggs in one basket.
Of course, a wide range of involvement can often result in timing conflicts.