What's the most counter-intuitive thing you learned in trading?

That only 6% of ET posters have edge but even if they revealed it, most people wouldn't be able to copy it.

 

And those who understand would give signals and sell it.

 

If you randomly day trade SPY (or any indices), say once a day, over a long period, e.g. a decade, you will likely be making money as a day trader. Of course I am ignoring commissions. You can backtest this yourself if you don't believe me.