>> Oh, it's a game all right. You want to make as many dollars as possible by playing the game right.
No, you don't. You want to make as many dollars as possible regardless of what you're doing, be it trading stocks or otherwise. But with trading, you're risking what you already have, so you want to invest, and not confuse the word investing with gambling. And with that, it's entirely possible that not investing in the stock market whatsoever may be your best option throughout your whole life, if you're a software developer. If you're not one, then try to run a business in a different area to learn about the way things work, while saving your money to make a very reasonable bet on a few bets, not feeling like you have to have your money tied in the stock markets just because other people do.
Now, if we knew that the stock market in general would go up 5-15% on average every year for the next 40 years, that would be different, and I would buy an index fund at the very minimum. But we do not know what will happen, nor can we even slightly base our financial decisions on what happened before. That would not be investing, that would be time machine traveling or being hopeful things will work out. And as software developers, we have more control over more things such that running one's own tech business while learning about new developments will put us in the right mindset to understand and evaluate the rare great buys in the stock market correctly, as well as how consumers think based on having first hand experience running a company oneself.
And true investing is not just putting money into "the stock market" void every month, but actually following developments and researching every week for at least an hour a week per stock (this is actually Cramer's advice.) And you want to have 5 stocks to diversify (Cramer's advice.) So with those 5 hours a week, could you not create and maintain a web app, or two or three? Have fun reading Hacker News like you normally might do, sure, whether you invest in stock or not. But just take the time you would spend researching and discussing the companies you hold (as well as new companies you might be interested in) and take that time to actually develop software. In either case, you might only make a few hundred or thousand dollars a year profit. That alone shows you might as well be investing in yourself. But that's not all!
With creating your own software, you learned new skills, kept current ones sharp, created a portfolio, became confident in yourself, and all of this may raise your salary by $20,000-$50,000 a year and work the same amount of hours, be confident in pursuing contracting opportunities based on the evidence you can create stuff, sell off various web apps you created, even for just a few thousand, and establish a reputation. So those hundred to thousand dollars a year, or any money made, or even a loss of $200-$500 a year due to web hosting and such and zero profit, can easily return ten, twenty, or thirty thousand dollars for a 21 year old, more than anything else, in just one year.
But with "investing" as a 21 year old, making a hundred or thousand dollars a year is about the best you could do. In fact, it is possible to lose the entire investment, as well. So the net return might be negative (e.g. you'd be better off not putting money in the stock market.) Subtract account fees as well. And now, subtract all that research you did, and how many hours you spent on it, at let's say $10-$30 an hour. And subtract the lost opportunity cost of being able to have used that time to create anything, anything at all for experience and other reasons I mentioned previously! Subtract the stress and worry!
Let's go nuts here. Even if you were guaranteed not to lose money you invest in the stock market, and you turn your $2,000 into $4,000, and let's say you did it by luck so you spent zero hours researching anything and just left your money in the account, investing the time and money towards furthering your own education is just a much better use of resources for a 21 year old, even in the best case scenario here.
And, as he mentioned he has debts, he should just try to pay them off. If the debt is at 7% for college, 15% credit card, and other, pay those off first!