A funnel is only as good as its leakiest step. Count how many people survive each stage, and the per-step rates multiply into your overall conversion โ while the worst single step shows where a fix would buy you the most.
Overall conversion is the product of the step rates, so a single weak step โ the funnel's bottleneck โ drags the whole chain down, and a 10-point fix to the worst step is worth far more than the same fix to a healthy one.