We want to ensure your funnel analysis is as accurate and clear as possible. This article explains a known limitation that can affect your Time-to-Completion metric when defining funnel steps.
What are overlapping steps?
Overlapping steps occur when the conditions you define for two or more consecutive steps in a funnel are both satisfied by the same page view or event within a user's session.
This happens when your step definitions aren't mutually exclusive, meaning a single user action can match the criteria for multiple steps simultaneously.
How overlapping steps affect Time-to-Completion
When two steps overlap, the Time-to-Completion metric (the time taken for a user to move from Step N to Step N+1) can produce unreliable results. You'll notice one of three suspicious values that indicate overlapping steps:
| Indicator | What you'll see | Why it happens |
|---|---|---|
| 0 seconds | The reported time is exactly zero (or a negligible fraction of a second) | The system found a single event or pageview that satisfied the conditions for both the current step and the previous step at the exact same timestamp |
| Abnormally high values | The reported time is many hours or days (e.g., 9999 hours) when you'd expect minutes | The system incorrectly matches the current step to a very old, unrelated event or pageview that happened before the previous step's true event |
| Negative values | The reported time is a negative number (e.g., -5 seconds) | The system incorrectly finds a subsequent step's matching event that happened before the previous step's event was correctly identified |
In all three cases, the metric doesn't reflect meaningful user behavior and can skew your analysis.
Example: How overlapping occurs
Let's look at a funnel designed to track a customer's journey from adding items to viewing shipping options:
| Funnel step | Condition (based on pageview custom variable cvar_1) |
|---|---|
| Step 1 (Cart View) | cvar_1 CONTAINS the phrase "Cart" |
| Step 2 (Shipping Info) | cvar_1 EQUALS the phrase "Cart - Shipping Address" |
Now consider a pageview tagged with the value: "Cart - Shipping Address"
- Does it match Step 1? Yes, because "Cart - Shipping Address" CONTAINS "Cart"
- Does it match Step 2? Yes, because "Cart - Shipping Address" EQUALS "Cart - Shipping Address"
Since a single pageview satisfies both Step 1 and Step 2, the system can't reliably distinguish the order. This results in both steps having the same timestamp, producing a Time-to-Completion of 0 seconds for the Step 1 → Step 2 transition.
How to fix overlapping steps
If you notice a 0-second, negative, or abnormally high Time-to-Completion between two steps, use one of these workarounds:
Refine step defintions to be mutually exclusive
This is the most effective solution. Ensure the criteria for a step cannot be met by an event that also meets the criteria for the previous step.
How to do this: Explicitly exclude the previous step's conditions. In the scenario above, change Step 1's definition to:
Step 1: cvar_1 CONTAINS "Cart" AND cvar_1 DOES NOT EQUAL "Cart - Shipping Address"
Introduce an intermediary step
If the pages are truly distinct but your tagging is too broad, add a specific event that happens between the two pages.
How to do this: Insert a step that tracks a highly specific action (e.g., a "Click to Proceed" event) between your overlapping steps. This forces a temporal gap in the funnel path, ensuring the time calculation is based on distinct events.
Use stricter operators
Whenever possible, use an EQUALS operator instead of broader operators like CONTAINS or STARTS WITH to minimize unintentional overlap.