It's better to make mistakes early and learn. Because in a typical 40 year investment journey, the most compounding will take place in the last decade.
Carrying poor investing habits like stock picking, speculation, market timing, and using trading tools like options, margin, leverage into your later years will be too dangerous and costly since you lose the ability to recover from financial losses.
While any portfolio can go up by a million percent, it can only go down by 100 percent. So a portfolio should be defensive in nature. It's better to have good investment habits that last your life time than be rewarded early on in your life with your poor investment habits which then turn to destroy you in the end.