Lightning churn is the process of constantly adjusting channel liquidity—closing channels, opening new ones, or rebalancing funds to maintain capacity. While some amount of churn is normal, excessive churn can drive up on-chain fees and counteract LN’s benefits.

For instance, if users frequently close channels as soon as they receive or send payments, they’ll repeatedly pay Bitcoin transaction fees. Well-managed LN setups mitigate churn by predicting liquidity needs, using rebalancing strategies, or relying on splicing (when implemented) so that channels last longer and require fewer on-chain transactions. The goal is to strike a balance between channel flexibility and the cost of frequent changes.