No matter how I make money I always wory tomorrow it wil lall stop..then what? Are you the same with your day trading? Worry about your method will start losing money? What would you do? Do you have a job/career/ investments you can fall back on?
the more complex a strategy is, the more prone it is to stop working... build your trading plan upon general principles which work in (almost) every market condition...
I'm still looking for... seriously, from time to time I have also these worries like you... Who knows what's going to work in 20 years? Since they started this huge machine yesterday in Geneva we'll fall into a black hole anyway...
The market has always made sporatic "shifts". That's why an investor can go along for quite a while having success, then have trouble and not have changed his behavior. When things are working, you need to make something of it. Then be on the look-out for when that no longer works and you have to "go back to the drawing board". It has always been thus.
You probably need at least 2 kinds of systems: a trend following system and a mean reversion system. At least you'd be covered for the 2 main market conditions: trending and chop.
I worry about this constantly. When sh!t gets choppy and unreadable I think to myself, "is the party over?" I have no intentions of going back to grind and have learned that patience, whether for a day, a month, or many months, is something that must be learned and constantly applied. If stuff isn't working, stop and be ready to not make money for a bit. My boss has been a scalper / day trader for 25 years. Everytime the market changes, he tells me, "they will be back." So far for the past 9 years, he has been right.
I'm way more concerned with myself not following my method than I am about the method itself failing.