Simple example. Previously, I tried to balance channels using fees. I had an algorithm where if a large portion of the channel's funds was on my side, I set fees low until the balance shifted more toward the remote side. Once, I encountered a situation where I couldn’t send a payment to a seller through my nodes. I investigated and found that my wallet was receiving an error stating that the fee on one of my nodes didn’t match the fee the wallet obtained from the network graph. In other words, the node had a higher fee than what my wallet had in its data. I continued to investigate and discovered that the node had raised the fee several hours ago and reported it to the network via the Gossip protocol, but my wallet, which was always connected to the network at that time, did not receive this update and still had the old information.

I don’t remember all the exact details of that case now. I know that in the packet returned to the sender in case of an error, the new fees present on the node at that moment are included. But for some reason, my wallet didn’t set the new fee and didn’t resend through that node. I don’t recall why that happened. However, while studying that case, I concluded that balancing channels using fees has significant drawbacks because the fee percentage changes over time, causing many payments that could have gone through to fail. Subsequently, I at some point made the fees on channels fixed.

Later, after some time, I had the thought that balancing using fees probably has a logical flaw. Because when we have a large balance on our side, effectively locking up a large portion of our funds, logic suggests that this is an ideal scenario to earn fees. But channel balancing pushes us to use minimal fees in such cases. And channel balancing also pushes us to raise fees when liquidity in the channel is running low. From a logical standpoint, I think it should be the opposite. From a profitability standpoint, that is. A node should earn fees specifically when it has a balance in the channel and not earn them when it doesn’t.