A Caution on Market Analysts A Caution on Money Managers Who Have Been Successful

A Caution on Market Timing Strategies

Although market timing is an approach that millions of investors pursue every day on exchanges around the world, the truth is that it tends to carry more risk than reward. With the erosion of profits due to transaction fees and the bid/ask spread, market timing tends to require larger investments of capital in order to be worthwhile. While no investment strategy for buying stocks has proven to be risk-free and a sure thing, there are other options that tend to be safer investment alternatives. 
Source: http://www.investorguide.com/igu-article-977-stock-strategies-buying-stocks-using-growth-strategy.html