- /// Note that if the preimage is not known or the amount paid is incorrect, you must call
- /// ChannelManager::fail_htlc_backwards to free up resources for this HTLC.
+ /// Note that if the preimage is not known or the amount paid is incorrect, you should call
+ /// ChannelManager::fail_htlc_backwards to free up resources for this HTLC and avoid
+ /// network congestion.