<<you mean reverse engineer a financial target (requirement) eg $5m by age 60? and then take that into designing and trading a system accordingly including factors such as position size and expectancy? >>
That's one way to do it I suppose. Again, it depends entirely on what you are trying to do - and there are as many "criteria" as there are people I suppose, and a criterion can have one (e.g. "Make as much money as possible in 2018, all else be damned!") or many facets ("Make 10% in 2018, without exceeding a 20% drawdown, without paying more than 6% to create such a hedge, and keeping within a Sharpe ratio of X, with no more than 10% exposure to any one sector...andd yah balh blah ybbidt blibbidy").
It ALL depends on what you are trying to accomplish, and that includes not having an open-ended time frame.
And once someone defines their criteria specifically, like this, that is what dictates not only their money management, but their trading as well.
I know it sounds dry, plain, boring, pedestrian, as sexy as sweat sock and not worth anyone's time to do. The rejection of doing this, at the outset, however, is indicative of how serious someone really is about tradin OR if they are like the guy at the casino with his life savings who thinks he is there to make money, but, actually, is there for just expensive entertainment.
And having a criteria, and the degree to which is is specified, I have found to be the biggest determinant to success or failure at any of this.
Most interesting post. I had not even considered this. Usually what I have read is to just follow the process and the market will give whatever it does but never have I thought of planning and defining my trading system as per defined needs or wants.
Thanks again