SaaS products have a natural tendency to accumulate complexity. Every quarter, features are added. Very few are removed. The product that started with 20 coherent features reaches 80 features, many of which are used by less than 10% of customers, some of which contradict each other, and all of which add cognitive overhead to anyone trying to understand what the product actually does.
This accumulation is the product debt that doesn't show up in technical debt metrics but manifests in longer onboarding times, higher support volume, and worse new-user retention.
The kill list is the antidote. It's a formal list of features and functionality candidates for removal, with criteria for decision-making and a process for deprecation.
How to build your kill list:
Feature usage audit. Pull usage data on every feature in your product. Any feature used by fewer than 10% of active users is a kill list candidate. Any feature used exclusively by 1-2 enterprise customers who specifically requested it is a custom integration, not a product feature.
Feature conflict audit. Where in your product do two features do similar things? Where did you build a new capability without removing the old one? Consolidation opportunities are kill list candidates.
New-user journey audit. Have someone unfamiliar with your product attempt to complete the primary onboarding workflow. Every point of confusion, every feature that confuses them before they need it, every menu with options they don't understand yet — these are kill list candidates for restructuring.
Deprecation process:
Announce 90 days before removal. Most features used by < 10% of customers can be deprecated with minimal customer impact if you communicate clearly and migrate any customers who depend on it.
Replace with something better, not just removal. The kill list isn't about subtraction for its own sake. It's about replacing complexity with clarity.
A simpler product is almost always a more retentive product.