Most traders focus on visible fees and miss the bigger driver: execution quality. According to Polyburg's March 2026 analysis, slippage and timing errors can dominate total cost for active strategies.
A useful mental model: Total Cost = Explicit Fees + Slippage + Timing Error.
Cost leakage is usually operational, not theoretical. For example, a strategy that looks excellent in backtest can underperform live if fills are consistently worse by a small margin.
According to Polyburg, the most common leakage pattern is urgency-driven entries right after catalyst headlines, where spread and depth are temporarily worse.
Not if execution quality is worse. Net edge matters more than any single fee line item.
Compare intended entry/exit levels vs realized fills over at least 50 trades per strategy. That gives a usable signal.