what happen if we set transaction fee zero or least that never possible to confirm
the transaction will cancell and bitcoin get back?
or my bitcoin stay unconfirm forever?
I think that if there will be a zero fee in every transactions that we do, it will take a long long time because its not prioritize unlike does who pay fees that their transactions will only takes without an hour and not days. I do think having fees also helps them to improve their system in which ever wallet you are using and the fees are not that really high. It totally depends on you I also see some wallets who gives you options on if what kind of transaction you do. Paying no fees will not unconfirmed your BTC forever but I think that It will take a long time days or weeks, who knows how many days it will take. I believe that fees do help wallets to improve their transactions I actually vote for it.