Thanks for kind words @madmacs. I've been out of the business...

Thanks for kind words @madmacs. I've been out of the business for some years, until the last 15 months or so. I'm also new to HC, and I didn't know there's an Education section.
Actually, what I meant was that you "only " need a certain ratio of winners to losers to come out ahead., say 6, 7  out of 10 would be great. Which was in the context that there HAVE to be losers, and you really don't care (easier said than done, but it's correct), since there's no way you can possibly know what will be a winner, and what will be a loser, even with a back tested system. The outcome of every trade is random. This is why you don't need to know what will happen next, how this started. You can't, and it doesn't matter. The aggregate result, over time, if give a chance to run its course before you have a few losers, panic,  and say "forge it"should not be random, but should reflect your bask tested system ("edge"). Note that this was before and independent of Taleb's "Fooled by Randomness", and the monster seller "The Black Swan", a phrase which has now entered the language. Interestingly the series (of three) is called "incerto".....uncertainty.
This (randomness, not caring) is part of Douglas' 5 inviolable truths, specifically.  (I also realize the Buddha has his 4 Noble Truths) which I will reproduce here, and maybe can discuss elsewhere, more appropriate

Not necessarily 6 (or 10)  running at a time, no, but many do, and probably intra-day...too complex, as you've  indicated (if done manually and not automated). I suggest people over-trade. I'd say that most professionals a) focus on futures due to the leverage (called CFD in Australia {the only thing you can short with CommSec}, BUT even they not permitted in Super, just as Margin is not, and by implication, shorting is not). CFD's are aggressively promoted in Australia (and banned in most countries).
But I digress.
Further, if you look at many of the TA texts, the examples are  - typically - also taken from futures. People tend to specialize in one or two things , that's it. Like Oil, or Currency (one pair, or several), whatever, you get the idea. They know one important thing (very well) like the Hedgehog, unlike the Fox who knows many things (less well). Personally, I think stocks s*ck. Too many things that are outside your control: earnings disappointment, analyst downgrade, corporate malfeasance, whatever. But that's what I do now, and only long (in Super - no savings sadly, but that's personal, for now ).
Here are Douglas's 5 Truths . I know they sound oracular, like vapid  highly paid "consultant-speak", (a wise man told me so, but he thought he knew more about markets than he did), but that would be very wrong. We can discuss in another time, in another place (apologies to Van Morrison). This would later be followed by the "Seven Principle of Consistency", of disciplined Trading, more down to earth.
But one one must understand and internalize these

1. Anything can happen
2. You don’t need to know what is going to happen next in order to make money.
3. There is a random distribution between wins and losses for any given set of variables that define an edge.
4. An edge is nothing more than an indication of a higher probability of one thing happening over another
5. Every moment in the market is unique