Keep a simple three-column log: date, what rule you broke, and the cost in R. Review it weekly. If a mistake appears 3+ times, it's a discipline leak you need to fix in your checklist or rules. Most traders find one mistake repeated 20+ times that costs 40% of their drawdown.
- One repeated mistake costs more than a bad setup
- Most traders break the same 2–3 rules over and over
- Making the log is easy; reading it and changing is hard
- Visualizing the cost of a rule break changes behavior
The difference between traders who break even and traders who consistently profit is rule adherence. The mistakes log holds you accountable.
The simple format
Create a table with three columns:
| Date | Mistake (rule broken) | Cost in R |
|---|---|---|
| 09/24 | Entered a setup not on my watch list | −1.0R |
| 09/24 | Traded after hitting 3-trade daily limit | −0.8R |
| 09/26 | Took a trade 3 min before econ data | −1.2R |
| 09/27 | Averaged down into a losing trade | −1.5R |
| 10/02 | Entered after 2 consecutive losses (revenge trade) | −0.9R |
| 10/04 | Position size $1,500 instead of $1,000 (oversized) | −0.7R |
| 10/05 | Exited winner at target instead of trailing stop | +0.4R |
| 10/06 | Entered the same setup twice in 30 min (no space between) | −0.6R |
Five columns max, or you'll skip it.
Why the mistakes log works
Reason 1: It makes violations visible
You're breaking rules anyway. The log just makes you face it.
"I only averaged down once" → you think. "I averaged down 4 times and it cost me −3.2R" → the log shows.
Seeing the cost in R (not dollars) is powerful. −1.5R looks worse than −$75.
Reason 2: It identifies repeats
After 30 trades, sort by mistake type:
| Mistake type | Frequency | Total cost |
|---|---|---|
| Revenge trading (after loss) | 7 times | −6.1R |
| Trading outside golden hours | 5 times | −3.8R |
| Averaging down | 4 times | −4.2R |
| Position sizing | 3 times | −1.9R |
| Entering off-watch-list | 2 times | −1.5R |
Revenge trading is the #1 leak. Cost: −6.1R. That's your focus.
Add a rule: "Stop trading for 1 hour after a −2R+ loss."
Test it for 30 days. Did revenge trades drop? Did costs drop?
Reason 3: It separates setup failures from discipline failures
| Mistake | Category |
|---|---|
| Took a breakout; it failed | Setup failure (sometimes happens) |
| Took a breakout, but it wasn't on my watch list | Discipline failure |
| Averaged down and lost | Discipline failure |
| Position size was $1,500, rule is $1,000 | Discipline failure |
Setup failures are fine if your expectancy is still positive. Discipline failures are kills. One repeated discipline mistake might cost more than 10 setup failures.
Your Journal Should Find the Pattern for You
TRADZY's TradLog tags every trade by setup, session and emotion, then shows where your edge actually is.
Start Your Free Journal →What to log
Log only rule breaks, not losses. A loss can be:
- A good trade that lost (acceptable, don't log)
- A rule break that lost (log it, fix the rule)
| Entry | Log? | Why |
|---|---|---|
| Took an A-grade breakout, plan followed, lost −1.0R | ❌ No | Good decision, bad outcome. Acceptable. |
| Entered without volume confirmation, plan wasn't verified | ✅ Yes | Rule break. Fix checklist. |
| Took a fourth trade when limit is 3 | ✅ Yes | Discipline failure. |
| Traded GBP/USD at 11:45 AM, my worst time | ✅ Yes | Time-of-day rule break. |
| Entered 2 minutes after data release, rule is 5 min | ✅ Yes | Timing rule break. |
| Oversized position by $200 | ✅ Yes | Sizing rule break. |
Analysis at week's end
Step 1: Count frequency
| Mistake | This week | Last 4 weeks | Trend |
|---|---|---|---|
| Revenge trading | 2 | 12 | Getting worse? |
| Timing (bad hours) | 1 | 5 | Getting better ✅ |
| Position sizing | 0 | 3 | Fixed ✅ |
| Data-release trades | 2 | 8 | Still recurring |
Step 2: Calculate cost of top 3
- Revenge trading: 12 times, −6.1R → −0.51R per mistake
- Data-release: 8 times, −4.8R → −0.60R per mistake
- Total cost: −10.9R on last 50 trades
Without these two mistakes, you'd be +$X instead of $Y.
Step 3: Design one fix
Don't try to fix all 3. Pick one.
Fix: Add a timer to your chart software. Phone alert: "Alert: 2 minutes before data release. No new trades."
Test: For the next 30 days, track whether data-release trades drop.
Rules that reduce mistakes
Once you identify a leak, add a rule to your checklist:
| Leak | Vague rule | Specific rule | Mechanism |
|---|---|---|---|
| Revenge trading | "Don't revenge trade" | "After −2R loss, stop for 1 hour" | Phone timer, chart note |
| Bad hours | "Trade better hours" | "No trades 11:30 AM–1:30 PM ET" | Phone alarm, chart clock |
| Data news | "Avoid data" | "No entries 2 min before or 5 min after econ data" | Calendar marked, timer |
| Oversizing | "Size correctly" | Formula: (account × 1%) ÷ (entry − stop) | Spreadsheet, pre-calculated on watchlist |
| Off-watchlist | "Stay on plan" | "Watchlist only; mark 9 AM with symbols" | Printed watchlist on monitor |
Each rule needs a mechanical trigger, not willpower.
Common mistakes (and how to log them)
| Mistake | Log entry |
|---|---|
| You took a trade that wasn't on your watch list | Date: X, Mistake: Entered off-watchlist (AAPL unplanned), Cost: −0.8R |
| You sized a position larger than your formula allowed | Date: X, Mistake: Oversized $1.2K vs rule $1.0K, Cost: −1.0R |
| You broke your daily loss limit and kept trading | Date: X, Mistake: Hit daily limit, kept trading anyway, Cost: −0.7R |
| You entered a setup but your setup definition didn't match | Date: X, Mistake: Setup ambiguous; broke clarity rule, Cost: −0.6R |
| You traded 3 minutes before economic data | Date: X, Mistake: Entered before data, +3 min buffer rule, Cost: −1.5R |
| You averaged down on a losing trade | Date: X, Mistake: Averaged down (rule: add only on winners), Cost: −1.4R |
Mistakes that are actually trades
Some "mistakes" aren't rule breaks, they're just losses:
❌ "I took a trade that looked good but it lost −1.0R" → Don't log this. It's variance.
✅ "I broke my time-of-day rule and entered at 1:15 PM (when I know I lose)" → Log this. It's a discipline failure.
Reviewing after 100 trades
| Data to track | Question | Action if yes |
|---|---|---|
| Any mistake >10 repeats? | Is there a leak I'm not addressing? | Make a rule. Add it to checklist. |
| Any mistake appearing for the first time at trade 90+? | Am I getting sloppy as I get tired? | Add a rest day to your trading schedule. |
| Any pattern: mistakes cluster on certain days? | Do I trade worse on Mondays? After down days? | Use that insight to reduce size on those days. |
After 100 logged mistakes, you'll see two patterns:
- The core leak (usually one mistake repeated 20–40 times, costing 30%+ of drawdown)
- The small leaks (various mistakes, 2–5 times each, costing <5% each)
Fix the core leak. Ignore small leaks unless they grow.
FAQ
Should I include winning trades where I broke the rule?
Yes, log them. Mark as "+cost" instead of "−cost." Example: "Entered off-watchlist, plan broken, but won +1.0R." This shows rule breaks that got lucky (dangerous; teaches wrong lesson).
How do I track cost in R if I'm not using R yet?
Convert: cost in dollars ÷ risk per trade = cost in R. Example: Lost $150, risk was $100 per trade, cost = −1.5R.
Should I log emotional trades or only rule breaks?
Log rule breaks only. Emotions are separate; you'll track them in your emotional state field in the journal. Here, focus on measurable violations.
What if I make a mistake but it wins?
Still log it. Mark it "+cost" instead. Example: "Rule break: +1.2R (got lucky)."
How often should I review the log?
Weekly (30-min review). Monthly (full analysis, calculate top leaks).
What if I have too many mistakes?
That's actually good data. You see where discipline is weak. Pick the #1 leak, fix it for 30 days, then move to #2.
Put This Into Practice
- Log your next 20 trades with setup, session and emotion tags
- Let the TradLog surface your best and worst setups
- Run the weekly review and cut one leak
Start Free in TRADZY →
Educational content, not financial advice. Trading involves substantial risk of loss.