Winning traders are not the ones with the most exotic strategies — they are the ones who avoid the obvious mistakes everyone else keeps making. Almost every blown account traces back to the same short list. Here it is, with the fix for each.
The account-killers
Oversizing. Putting too much on one market is the single fastest way to blow up, because losses compound. The fix: a hard per-position cap from your bankroll plan — typically 1–5% — that you never breach, however certain you feel.
Chasing losses. Increasing your stake to win back what you just lost is how a bad day becomes a catastrophe. The fix: decide your stake by your edge, never by your recent results. A loss is not a reason to bet more.
Ignoring fees and spread. On thin markets, the gap between buy and sell prices plus trading fees can quietly erase a real edge. The fix: net costs out of every trade before you take it — the profit calculator makes this quick.
Misreading resolution rules. Being right about the event but wrong about how the contract settles is a uniquely painful way to lose. The fix: read the exact resolution criteria first — what counts, which source decides, and what happens in edge cases.
Trading without an edge. Buying because a market is exciting, not because you think the price is wrong, is just paying the spread for entertainment. The fix: if you cannot explain why the price is mistaken, do not trade. See how to find value.
Overtrading. Forcing action when there is no good opportunity bleeds your bankroll through costs and marginal bets. The fix: treat patience as a position. The best traders pass on far more markets than they trade.
Trading on emotion. Backing your favourite team out of loyalty, or revenge-trading after a loss, replaces analysis with feeling. The fix: separate fandom from trading, and step away when you notice yourself trading to feel something rather than to profit.
Longshot bias. Cheap contracts at 2–3¢ feel like lottery tickets, but they are usually priced about right and are hard to exit. The fix: only take longshots when you can articulate why they are genuinely underpriced, and remember you need them to hit far more often than feels intuitive.
A pre-trade checklist
Before you confirm any trade, run through five quick questions:
- Why do I think this price is wrong — specifically?
- Is this position within my per-position cap?
- Have I accounted for fees and the spread?
- Do I understand exactly how this market resolves?
- Am I trading on analysis, or on emotion?
If any answer gives you pause, skip the trade. There is always another market. Combine this with solid bankroll management and sensible position sizing, and you will already be ahead of most of the field.
Chasing losses and emotional trading are also warning signs of a gambling problem. If trading is causing you harm, please read our responsible trading page — in the US, free confidential support is available at 1-800-GAMBLER.
Related strategies
Build on this approach with the adjacent playbooks:
Frequently asked questions
What is the most common prediction market mistake?
Oversizing — putting too much on a single market — is the fastest way to blow up an account, because losses compound. A hard per-position cap of 1-5% of your bankroll is the simplest protection.
Why is chasing losses so dangerous?
Because it decouples your stake from your edge and ties it to your emotions instead. Increasing size to win back a loss turns a bad day into a catastrophe. Your stake should be determined by the quality of the opportunity, never by recent results.
How can I avoid these mistakes?
Run a quick pre-trade checklist: know why the price is wrong, stay within your position cap, account for fees and spread, understand how the market resolves, and confirm you are trading on analysis rather than emotion. If anything gives you pause, skip the trade.