Judge the decision, not the profit: resulting, outcome bias, discipline score

A winning trade doesn’t mean you decided well, and a losing trade doesn’t mean you decided badly. It sounds obvious, but the brain does the opposite almost every time. When a trade closes in profit we remember the method as good. When it hits the Stop loss we want to change the rules. This article covers what this habit is called, why one trade’s result tells you far less than you think, and how to swap “I must be green today” for a goal you can actually control.

Resulting: judging a decision by its result

Annie Duke, a former professional poker player, writes in Thinking in Bets (2018) about a term poker players use: resulting. It means judging whether a decision was good or bad purely from how it turned out. Her opening example is an American football coach who called a pass play at the end of the 2015 Super Bowl. The pass was intercepted and the call was widely labelled one of the worst ever. Her point is that if the pass had been caught, the same decision would have been praised as brilliant.

Her core idea is that every outcome is a mix of two things: decision quality and luck. In games with a lot of luck, like poker or trading, a single result can’t separate the two.

Psychologists call the same thing outcome bias. A frequently cited study is Baron and Hershey (1988) in the Journal of Personality and Social Psychology. Participants read about medical decisions where the information available at the time was identical and only the outcome differed. They rated the very same decision as better when it turned out well.

Outcome bias is slightly different from hindsight bias. Hindsight bias is feeling you “knew it all along” once you know the result. Outcome bias is using the result to grade the quality of the decision. The two often travel together. Read about the first in Hindsight bias and past charts.

The 2×2: decision × outcome

Every trade lands in one of these four boxes. A “good decision” here means following the plan you wrote before entering, and that plan has already been tested.

The box that costs money in the long run is not the losing box. It is broke the plan, made money. The brain learns from rewards, so a trade like this teaches it that entering without a setup or raising the size “works”. The second box to watch is did it right, still lost, because the usual response is to change the rules, even though losing trades are already part of a good system.

One trade, or one week, tells you very little

Let’s simulate two rules. Both make +2R on a win and lose −1R on a loss (R is the risk you set per trade). Only the win rate differs.

• +EV rule: wins 40%, expected value = 0.4 × 2 − 0.6 × 1 = +0.2R per trade
• −EV rule: wins 30%, expected value = 0.3 × 2 − 0.7 × 1 = −0.1R per trade

Worked example for a 5-trade period (assume 1 trade per day, so 1 week). Total = 2 × wins − 1 × losses.

1. The +EV rule loses over the week when it wins at most 1 trade. Chance = 0.6⁵ + 5 × 0.4 × 0.6⁴ = 0.078 + 0.259 = 33.7%
2. The −EV rule is profitable over the week when it wins 2 or more. Chance = 1 − 0.7⁵ − 5 × 0.3 × 0.7⁴ = 1 − 0.168 − 0.360 = 47.2%

The other periods use the same binomial calculation, checked against a 200,000-run random simulation, which gave the same numbers.

Period	Trades	+EV rule loses over the period	−EV rule profits over the period
1 day	1	60.0%	30.0%
1 week	5	33.7%	47.2%
1 month	20	25.0%	39.2%
1 quarter	65	12.7%	29.0%
1 year	250	1.6%	12.1%
4 years	1,000	under 0.1%	1.1%

Read this table slowly. The losing rule has a profitable week almost half the time, and still finishes almost 1 quarter in 3 in profit. The clearly winning rule still has a losing month 1 time in 4. And +0.2R per trade is a big edge. Most real systems have a thinner one, which makes the misleading stretches even longer.

If you judge a rule by one week’s result, you will throw away good rules and fall for bad ones about equally often.

See how to work out how many trades are enough in How many trades do you need, and watch for the reverse, where a winning streak breeds too much confidence, in Overconfidence after a winning streak.

Two separate questions: is the plan good, and did I follow it?

If one trade’s result is useless, what do you judge instead? Split it into two layers, each with its own kind of evidence.

1. Does the plan have an edge? Judged over many trades, in the hundreds, using Expectancy and the win rate against the break-even. See A high win rate doesn’t mean profit
2. Did this trade follow the plan? Judged right away on every trade, with no need to wait for the result, because the answer is in your hands before you click

The second layer is 100% in your control, and it is a precondition for the first. If you follow the plan only half the time, the totals you see aren’t the plan’s results. They are the plan mixed with emotion, so they can’t tell you anything about the plan. The plan you judge against has to be written down clearly first. Read Write your trading plan as rules.

One caution: following the plan perfectly can’t turn a losing plan into a winning one. A high discipline score on an untested plan just means losing in an orderly way.

Outcome goals vs process goals

An outcome goal, like “make 20R this month” or “no red days”, sounds motivating. But in the table above, even the good rule has a losing month 1 time in 4. A goal like that can fail when you do everything right, and as the deadline nears, people tend to raise their size or take trades with no setup to catch up.

A process goal is entirely in your hands, for example “every trade scores 5 out of 5 on plan adherence”. A practical way to do it is to score every trade, 1 point per item.

Item	Question	When to score it
1	This setup is in my written plan	Before entering
2	Position size matches my set risk, e.g. 1%	Before entering
3	SL (and TP if the plan has one) set at entry	Right after entering
4	Held and closed by the rules: no moving SL away, no fear exits outside the rules	When closing
5	Traded in a state the plan allows (within the daily loss limit, not in a banned window) and journal filled in	When closing

Items 1–3 are scored before you know the result, so profit can’t leak into them. For items 4–5, scored at the close, ask yourself “how would I score this if I didn’t know whether it won or lost?” Then keep the score as a column in your trading journal.

Example: an adherence log, 20 trades over 4 weeks

Looking only at profit, whoever kept this log would decide week 2 was a good week and week 3 means the system needs fixing. Both conclusions are wrong. Look closer at the numbers.

• 14 trades scoring 4–5: total +2.5R, average +0.18R per trade
• 6 trades scoring 3 or less: total +2.5R, average +0.42R per trade

In these 20 trades, breaking the plan looks like it “paid”. That is resulting happening inside your own journal. Six trades are far too few to tell you anything, and part of the rule-breaking profit came from taking more risk than the plan allowed, like trade 7 with its raised size. Trades like that can win several times, until the day they lose, and then they lose bigger than normal. Trade 9, where the SL was moved away and the loss grew to −2R, is that day.

How to use this: set a weekly average target, for example 4.5 or higher, and wait for a few hundred trades before comparing the average result of high-score trades with low-score ones. Meanwhile, what you can judge right now is the score line, which in this example improved from 2.4 to 4.8 while weekly profit swung back and forth.

Outcome-blind review

A technique most traders have never tried is reviewing a trade without seeing the result first.

1. Open the chart screenshot at the entry, without scrolling to the candles after it
2. Hide the profit and loss column in your journal
3. Re-score the trade on the 5 items, using only what was known at that moment
4. Then reveal the result and compare. If winning trades always get a higher score once you see the result, the result is quietly doing the scoring for you

Letting go after the click

Once you are in a trade, almost everything you control is done. Setup, size and SL are decided. What’s left is where the market goes, and nobody controls that.

The Thai word ปล่อยวาง (letting go) comes from the Buddhist teaching on non-attachment. It is often misread as not caring, or “whatever happens, happens”. The accurate meaning is to do your part fully, then not cling to the idea that things outside your control must turn out the way you want. Here it is used as a mental stance anyone can adopt, not a religious claim, and it fits trading well, because trading is deciding under uncertainty.

Your job ends when you click with the correct SL in place. The result of this trade belongs to the market. The result of hundreds of trades belongs to you.

As a routine after entering, it takes less than 2 minutes:

1. Check that the SL and TP are really where they should be
2. Score items 1–3 right away, before price moves far
3. Take two or three slow, long out-breaths, and tell yourself briefly “my part is done”
4. Set your alerts by the rules, then leave the chart. Don’t watch every candle. Checking results often makes the fear of losing stronger. Read Checking your account often hurts more
5. When the trade closes, score items 4–5 before looking at the profit or loss number

If your mind keeps circling an open trade, a short mindfulness practice can help a little. See Mindfulness for traders. And if trading results leave you anxious for long stretches, to the point that it affects your sleep or daily life, talk to a mental health professional. In Thailand, the Department of Mental Health hotline is 1323.

Profit still matters, in large enough numbers

This article isn’t telling you to stop caring about profit. The total over many trades is the only evidence that the plan really has an edge. What changes is the level at which you look. Per trade, look at discipline. Over hundreds of trades, look at the system. And a single trade that is clearly abnormal, such as a loss far beyond the SL, should be checked: was it news slippage, or did you move the SL yourself? That is information about your process, not about luck.

Common mistakes

• Changing rules after one loss. A loss on a well-executed trade is a normal cost. Rewriting rules after each recent result means no plan ever really gets tested
• Praising yourself after profit from a rule-breaking trade. This is the most dangerous box in the 2×2. Score it low honestly, even though it made money
• Setting daily or weekly profit targets. A good rule can still lose about 1 week in 3. Targets like that push you to raise size when you’re about to miss
• Scoring discipline after seeing the result. Always score items 1–3 before you know the outcome, or the outcome will do the scoring
• Thinking a perfect score means a good system. The discipline score measures whether you followed the plan, not whether the plan has an edge. You need both layers
• “Letting go” of the SL itself. Letting go means not clinging to the result after you’ve done your part. It doesn’t mean skipping the steps that limit risk