A full-scale LN needs one transaction to get on the network, then loading and unloading can happen entirely on the network, as well as keeping the channel open indefinitely.
Obviously getting to that point will take quite a lot of work, but there is no reason why you ever need to close a payment channel unless someone is trying to break the rules (and if that happens, you'll be happy, because you'll end up with all of the money in the channel, which will more than pay for the TX fees for 2 more transactions to close then reopen the channel).
But (correct me if I'm wrong) payment channels are connected to particular sets of recipients, but not necessarily any and all recipients. Your money is locked into that channel until you close it. You might need to open a different channel to reach your actual recipient.
No, you are missing the "network" part of "Lightning Network" it uses an onion-routing-like protocol to allow you to pay "through" other people.
So if I have a channel with you, and you have one with coinbase, I can buy bitcoin from coinbase through you without ever opening another channel, entirely counterparty-risk-free.
And in that scenario if you "refuse" to relay my transaction, or you try to do something sneeky like broadcast an old transaction that we made where I had .1 BTC and you had .9 BTC, that's breaking the agreement we have made and I can broadcast a counter-transaction to the blockchain proper which gives me all of the money in the channel (1 BTC).
And if I try to backstab you by broadcasting the "give me all the money" transaction when you haven't done anything wrong, you have a "counter-counter-transaction" you can broadcast that forces all the money in the channel to you (1 BTC). (and the counter-counter-transaction only works if you HAVE NOT broadcast the original transaction)
There is a bit more complexity to it, but that's the gist.
Easy peasy! Seriously, I've been skeptical of LN's success for its complexity. But reading your and others' comments here I can see that many people understand it clearly. It turns out I've been biased by my own ignorance. The more I learn about LN, the more hopeful I'm becoming. Thanks for helping.
Like most of bitcoin, it's a deceptively complex system made up of suprisingly simple parts.
I'm honestly still skeptical that LN will really take off (it needs the network effect to be useful), but the idea behind it is very elegant and solid.
If you're in the US, you might have heard of Starker exchanges (a.k.a. 1031 or like-kind). It's a method to defer realization of capital gains, usually on real estate. There are outfits that will help you form a multi-party exchange to match impedances between people who want to buy/sell properties, but some want to trade and some want to exchange for money.
Similar with organ donations. I might not match my wife's blood type, but I can donate a kidney to some other random person if there's a network that matches someone with my wife' blood type to her.
Counter-counter-transactions sound like textbook example of overengineering.
Bitcoin's only advantage at this point is its price, which will go away as soon as there is a crash. Then we can scrap Bitcoin, LN, and all the baggage and start with a clean 3rd generation crypto slate.
It's only overengineering if it is superfluous, and in this case it's not.
The counter-counter-transaction solves a very real problem and makes the entire system counterparty-risk-free. It's no more "overengineering" than your airbags are overengineering.
This is why the Lightning network is something more than just payment channels. If you have 2 or more channels open on the network, you are a node that can have payments routed through.
Same with trying to pay someone on the network whom you do not have an open channel with: the LN's purpose is to facilitate a network of channels.
Certainly hubs will form, but there should be many of them, and if there's a path to your recipient, you don't need a dedicated channel with them.
Obviously getting to that point will take quite a lot of work, but there is no reason why you ever need to close a payment channel unless someone is trying to break the rules (and if that happens, you'll be happy, because you'll end up with all of the money in the channel, which will more than pay for the TX fees for 2 more transactions to close then reopen the channel).