The worst thing to happen is to make a lot of monies right from the get go. Happened to me. In the dot com boom I had 100 shares of EMLX and 200 shares of TLGD. Do not remember the exact prices I paid but, long story short, I sold both stocks and made $25,000. That was a lot of money for me. All in cash in my bank account. I was stoked, treated about 60 people in the office for lunch at $18 per person in a Japanese restaurant buffet then. Not counting the soda and ice teas, I have generous tips on top of that. Went to Las Vegas 4 times in one year. Not a big gambler though, which was good. Then, I had 200 shares of CSCO at $120 and the market tanked and I kept losing monies on CSCO and my other investments. Buy and hold they said. Now, not only did I lose those monies I won but, my own capital on top of it. That is when I realized Buy and Hold as a strategy was crazy. CSCO closed on June 26, 2020 at $46.31. Had I held my positions, I would still be losing monies, 21 years after with nothing to show for it? Now, I know better and how to trade the stockmarket after all the expensive lessons. Eventually, you learn or you fail. Learning is better and making monies is sweeter.