It's really difficult to predict how investments like stocks and mutual funds will do in the long and short run. From the time I started investing, I didn't want to bother doing research and figuring out what stocks or mutual funds might end up being the most profitable.
I wasn't very knowledgeable about finances or how investments were influenced in so many ways by what was happening in the world around us.
So, I decided to hire an investment manager to do the work and choose what stocks and bonds I bought and sold. I could give him any output that I wanted. He kept up on all the information gathering and decisions about the purchase and sale of my investment. I'm confident that it's working better than I could do.