full disclosure: due to earning money in two different currencies (local + remote job) I must engage in forex market to some degree. This lasts for over 2 years now so I think I have some experience now. (Yes, it's a bit different than stock market, but still)

Almost everyone wins with toy accounts, but not with real money. People usually don't understand fully why that is. Let's get the obvious out of the way: on a toy account you think: "I'm going to test this strategy!" With real money you think: "f###, f###, f###! If I don't sell now and it drops more, I'm going to loose 3 months of income!" - that's the usual risk aversion everyone knows about. It's only devastating at the beginning - after a while you'll train it away to acceptable degree.

Now consider not-so-obvious stuff that doesn't happen with toy accounts and never goes away:

• you crashed your car and you need to sell some stocks at whatever price they're currently at to buy yourself a new one
• you found a bargain sale (say, a house) that you'll be able to resell for twice as much next year
• you came up with an idea for a new cool product. If you don't invest in it now, someone else will

In summary - the hidden cost of freezing your assets until your prediction/strategy is profitable (even assuming it's correct) is often higher than you'd like, not to mention time you need to put in evaluating this mess. This is the reason why I currently use forex only for hedging strategies (buy/sell currencies ahead of time at good price - when I know I'll need it in the future). But that's not even possible for stock market.

My advice: forget this thing. Just do what what you love and what you're good at: learn a skill or language, change job, start a business - invest in yourself! If you're not inherently interested in finance then stock market will be a waste of your time - you could use this time better (but not easier!) in your own field. Market offers a false promise of effortless gain.